Transcriber's Note:
Italic text is denoted by _underscores_ and bold text by =equal signs=.
All corrections in the ERRATA section below have been made in the text.
THE ORNITHOSAURIA:
AN ELEMENTARY STUDY
OF
THE BONES OF PTERODACTYLES.
Cambridge:
PRINTED BY G. J. CLAY, M.A. AT THE UNIVERSITY PRESS.
THE ORNITHOSAURIA:
AN ELEMENTARY STUDY
OF
THE BONES OF PTERODACTYLES,
_MADE FROM FOSSIL REMAINS FOUND IN THE
CAMBRIDGE UPPER GREENSAND,_
AND
ARRANGED IN THE WOODWARDIAN MUSEUM OF THE
UNIVERSITY OF CAMBRIDGE
BY
HARRY GOVIER SEELEY,
OF ST. JOHN'S COLLEGE, CAMBRIDGE.
_WITH TWELVE PLATES._
"_And when the appointed end comes, they lie not dishonoured in
forgetfulness_,"--Xenoph. _Memor._ Book 2, c. 1, § 83.
[Illustration: Cambridge:]
DEIGHTON, BELL, AND CO.
LONDON: BELL AND DALDY.
1870.
[_All Rights reserved._]
_The expense of printing this volume has been defrayed out of the Funds
of the Syndics of the University Press; and Professor Sedgwick hereby
expresses his grateful thanks to them for this great favour._
PREFACE.
This memoir is a portion of the Catalogue of the Woodwardian Museum
which has been made at Professor Sedgwick's request and at his cost.
When the Professor laid upon me his commands to prepare a Catalogue of
the Museum, it was planned in three distinct works. First, a series of
indexes to the specimens in the great divisions into which the Museum
is arranged; secondly, a series of memoirs upon the orders and classes
of animals concerning which new knowledge is given by fossils in the
Museum; and, thirdly, memoirs descriptive of those species contained
in the arranged collections which are at present unknown in scientific
writings.
For the convenience of students the Catalogue is made in parts. The
Syndics of the University Press printed last autumn as an example of
the "Indexes to the Museum," an Index to the Pterodactyles, Birds,
and Reptiles from the Secondary Strata. And this memoir is an example
of the second kind of Catalogue, which explains the structures of the
Pterodactyles of the Cambridge Greensand. In its progress questions
have arisen which necessitated an examination both of the method, of
research in comparative anatomy and of its results in classification.
And in so far as the views here advanced differ from those commonly
taught, the discrepancy is due to the writer's imperfect faith in the
results of the inductive method of research, as commonly used by modern
writers on Palæontology. It has not been consistent with the plan of
this little work to do more than scatter through it a few hints upon
method, a subject which will more fitly be discussed with a part of the
Catalogue which forms a synopsis of the osteology of the fossil animals
usually named Reptiles. The views here urged have however but little
of novelty. The name Ornithosauria was proposed by the distinguished
naturalist Prince Charles Bonaparte in 1838. The group as an order was
recognized by Von Meyer in 1830. The affinities of the brain appear
to have been detected by Oken, and the bird-like character of the
respiratory system was expounded by Von Meyer. And most of whatever
this memoir contains has been already thought or discovered by the
German philosophers, who have had the Pterodactyles as fossils of their
fatherland, though my own conclusions were arrived at separately and
from different materials.
The oldest Ornithosaurians are from the Muschelkalk of Germany.
In England the oldest are from the Lias,--several species of
Dimorphodon--a genus in some respects nearly resembling the
Pterosaurians of the Cambridge Upper Greensand. In the Oolite of
Stonesfield are several species of Rhamphorhynchus or a similar genus.
The great Pælolithic period from the Oxford Clay to the Kimeridge
Clay, has yielded in its several divisions small Pterodactyles of
new species. And the Psammolithic period from the Portland Sand to
the Lower Greensand has afforded many excellent remains both of true
Pterosaurians in the Purbeck, Wealden, and Potton Sands, and of animals
which indicate a new order of Ornithosauria having affinities with
Von Meyer's thick footed saurians, the Dinosauria. In the Cretaceous
series, Galt, Upper Greensand, and Chalk all have representatives
of the Pterosauria; but no English stratum has hitherto yielded
so many as the Cambridge Upper Greensand. From this formation the
collection accumulated during Prof. Sedgwick's long professoriate is
unequalled; though, excepting a few fine bones from the Chalk and
the Purbeck Limestone, the Woodwardian Museum is as yet deficient in
Ornithosaurians from the other Secondary Rocks. Until descriptions
of these animals shall have been published a classification of the
Ornithosauria must necessarily be provisional. And it cannot be
expected that descriptions of the structure of Cretaceous Pterosaurians
here given will hold good for all the Ornithosaurian sub-class.
Finally, I have gratefully to express my thanks to the many friends,
English and German, who have aided me with specimens and with their
writings; to the chiefs and officers of the English museums, especially
Prof. Owen, Prof Humphry, Prof Newton, Prof Phillips, Prof Flower, and
Prof. Huxley; to the officers of the University Library, especially
Mr Bradshaw, and Mr Crotch, for aid in consulting books; but chiefly
to Prof Sedgwick, who while employing me as his paid Assistant to
aid him in his Museum work, has generously encouraged me to carry on
for several years, without restraint and as part of my daily labour,
an investigation of which this treatise is the first fruit. Prof.
Sedgwick has placed at my disposal an ample number of copies for
distribution among those who take an interest in the Museum; and
especially among those who have contributed to the Ornithosaurian
collections, and aided me in my work.
_January 3, 1870._
CONTENTS.
_Page_
Introduction 1
Materials 1
History 3
Organization 7
Cuvier 7
Sömmerring 10
Oken 10
Wagler 11
Goldfuss 11
Wagner 14
Quenstedt 17
Burmeister 17
Von Meyer 17
Another view of the Ornithosauria 24
--------------
Osteological collection illustrative of modifications of Ornithosauria in
the Cambridge Greensand, pp. 28-94.
Sternum 28
Coracoid 32
Scapula 35
Humerus 38
Radius and Ulna 42
Proximal carpal 48
Distal carpal 50
Lateral carpal 51
Metacarpal bone of wing-finger 53
First phalange of wing-finger 56
Second phalange of wing-finger 57
Claw phalange 59
Os innominatum 59
Femur 62
Tibia 62
Tarso-metatarsus 63
Atlas and axis 64
Cervical vertebræ 65
Dorsal vertebræ 69
Sacrum 73
Caudal vertebræ 75
Bones of the head 77
Basi-oocipital bone 78
Back of the cranium 80
Back of another cranium 84
Ethmo-sphenoid 85
Mould of the brain-cavity 87
?Vomer 88
Quadrate bone 89
?Pterygoid end of palatine bone 91
Premaxillary bones 91
Lower jaw 91
Teeth 92
--------------
Conclusion 94
A summing up 94
Restoration 103
Speculations on habits and aspect 104
Notes on German specimens 106
Classification 108
Synopsis of species 112
--------------
Appendix 129
Index 133
Plates, and explanation of Plates.
ERRATA.
PAGE LINE
4, 2, from bottom, _for_ procælian _read_ procœlian.
7, 13, _for_ Ossements _read_ Ossemens.
8, last line, paragraph (2), _for_ outermost _read_ innermost.
10, 21, }
11, 5, } _for_ Sömmering _read_ Sömmerring.
11, 13, }
14, note, _for_ Beyerischen _read_ Bayerischen.
15, 5, _for_ ?zygapophyses _read_ spinous-processes.
17, 6, from bottom, _for_ Herman _read_ Hermann.
37, 5, from bottom, _after_ "spine as" _insert_ "are"
92, line above 'the Dentary Bone,' _for_ Pterodactyle _read_
Pterodactyles.
97, 11, _for_ Günter _read_ Günther.
99, 4, _for_ Ichthyopteria _read_ Ichthyopterygia.
101, 11, from bottom, _for_ procælous _read_ procœlous.
102, 15, _for_ procælous _read_ procœlous.
111, 8, _for_ Sömmering _read_ Sömmerring.
_For_ epipubic bone _read_ prepubic bone, pp. 61, 102, 109, 110, 111,
and pl. 8.
INTRODUCTION
TO THE
OSTEOLOGY OF THE ORNITHOSAURIA FROM THE
CAMBRIDGE UPPER GREENSAND.
--------------
Materials.
The Cambridge Upper Greensand has yielded to collectors bones which
illustrate nearly every part of the skeleton of the animals that are
commonly named Pterodactyles. Large collections have been acquired
for the Woodwardian Museum. A series of more than 500 bones have
been arranged to exemplify the osteology and organization of the
Ornithosauria in the area when the Cambridge Greensand was deposited.
And this memoir is written to explain briefly some of the structures
of the soft and hard parts of those animals which are exhibited or
demonstrated by these relics. Another collection of nearly 400 bones
has been arranged, which displays in association, as they were found
entombed in the old Greensand sea-bed, the remains of the skeletons of
thirty-three animals of the Pterodactyle kind. The whole of the remains
from this formation hitherto gathered cannot be computed to have
pertained to fewer than 150 individuals, which indicate a new sub-class
of animals, two new genera and at least twenty-five new species.
The bones were mostly of a paper or card-like thinness, and were
originally hollow like the thin bones of birds. In the jaws of other
animals, and in the sea, they were easily fractured, so that proximal
ends and distal ends and shafts and split bones abound, while perfect
bones are almost unknown. Even those bones like the carpals, which
almost retain their entirety, invariably show indications of having
been rolled on the sea-shore among the nodules of phosphate of lime
with which they now occur, in their angular margins being rounded, and
in the removal of slender processes. The rock in which these fossils
are found is a thin bed of chalky marl which is heavily charged with
dark-green grains of Glauconite, and is quarried largely, and entirely
dug away to be deprived of the dark-brown nodules of phosphate of lime
with which it is stored. In digging and in the subsequent washing, the
workmen, stimulated by an ample reward, pick out the fossils as they
are discovered. They are separated easily from the matrix of investing
marl, so that every aspect of each bone is seen, except for the
occasionally adherent oysters and the masses of phosphate of lime, with
which material the bones are also filled. Hence these remains afford
facilities for the study of the _joints_ such as no other specimens
have presented; and from their large size and comparatively great
numbers, render easy the labour of the student who seeks to contrast
them with the bones of other animals.
The osteological collection has been formed without regard to species
or genera, and arranged to exhibit the structure and organization of
the tribe of animals. So far as possible each bone, as humerus, femur,
&c., has its variations of structures and form contrasted on a single
tablet. The series comprises the following bones:
Fore-part of sternum. Coracoid (perfect). Scapula (nearly perfect).
Humerus (perfect). ?Radius (proximal end). Radius (distal end). ?Ulna
(proximal end). Ulna (distal end). Proximal carpal. Distal carpal.
Lateral carpal. Wing-metacarpal (proximal and distal ends). First
phalange (proximal and distal ends). Second phalange (proximal end).
Metacarpal or metatarsal (distal end). Claw phalange. Os innominatum
(parts of ilium, ischium, and pubis). Femur (perfect). ?Tibia
(proximal end). Atlas and axis. Cervical vertebræ. Dorsal vertebræ.
Sacrum and sacral vertebræ. Caudal vertebræ. Lower jaw (dentary and
articular ends). Premaxillary bones, &c. Teeth. Quadrate bone (distal
end with quadrato-jugal). Ethmoid with basi-sphenoid. Occipital and
parietal segments of skulls. Basi-occipital and basi-temporal. Cast
of brain-cavity.
They are exhibited in Compartments _a_, _b_, _c_ of the Table-case of
Cabinet =J=. The letter =F= in a circle is placed against figured
specimens.
History.
The Cambridge Pterodactyles first attain prominence in scientific
literature in the year 1859. Professor Owen had figured (plate 32, fig.
6-8) fragments of bones in the Palæontographical Society's Monograph
for 1851; the distal end of a large ulna (fig. 6); the shaft of a
phalange of the wing-finger, probably the first (fig. 7); and the upper
portion of the shaft of a small humerus showing part of the radial
crest (fig. 8). Inadvertently the last specimen was referred to the
Lower Greensand. But although fragments of humerus of Pterodactyle and
vertebræ of Pterodactyloid animals have in the last few years been
gathered from the Potton Sands, those deposits were believed to be
barren of fossils when Prof. Owen wrote; and all the Pterodactyles yet
made known from near Cambridge were collected from the Cambridge Upper
Greensand.
Among the earliest successful collectors were Mr James Carter, the
Rev. H. G. Day, St John's Coll.; Prof. G. D. Liveing, St John's Coll.;
the Rev. T. G. Bonney, St John's Coll.; and Mr Lucas Barrett, Trin.
Coll.; and the Rev. Prof. Sedgwick, Trin. Coll., on behalf of the
Woodwardian Museum. Mr Day and Mr Bonney both presented every specimen
from their cabinets which could enrich the University collection. And
in the last ten years the Woodwardian Museum has acquired, through the
skillful collecting of the Messrs Farren, the present materials. The
associated sets of bones were formed by William and Robert Farren,
who, obtaining the specimens from day to day as they were discovered,
were enabled to put together such parts of the skeleton as remained
together on the sea-bottom. These collections will hereafter be used
for the elucidation of species. They are the only materials which can
give the proportions of the Cambridge Ornithosaurians, and the contrast
of aspect which distinguished the living animals from those from other
rocks.
The other collections of these fossils are those of Mr William Reed
and Mr J. F. Walker at York, the Museum of Practical Geology, and the
British Museum.
The Woodwardian specimens as collected were placed in the hands of
Prof. Owen, and were first made known in the Professor's lectures on
reptiles and birds delivered at the Museum of Practical Geology in
1858. In that year Prof. Owen communicated to the British Association
for the Advancement of Science, and printed in their Report, the matter
of the memoir which was published with plates by the Palæontographical
Society in 1859. In this latter year Prof. Owen communicated to the
Royal Society an account of the vertebral column of Pterodactyles. In
1859 Prof. Owen also produced a classification of recent and fossil
reptiles at the meeting of the British Association, in which the
order Pterosauria appears with new characters--such as the pneumatic
structure of most of the bones--drawn from Cambridge specimens. In
1860 Prof. Owen produced another memoir on Pterodactyles, which was
published by the Palæontographical Society. A brief account of the
tribe appeared about the same time in the Professor's _Palæontology_.
In these writings are descriptions of the various parts of the
vertebral column. Their procœlian centra are described, and the
pneumatic foramina are noticed and supposed to have communicated
with air-cells. They are compared with birds, and distinguished from
birds; but although the order is classed with reptiles no contrast with
reptiles is made. Other bones described are a basi-occipital, and a
doubtful bone, then thought to be a frontal, but which is more like the
neural region of the sacrum.
The sternum is compared with the sternum of the birds Apteryx and
Aptenodytes, is stated to be formed, in the main, on the Ornithic type,
and to possess distinct synovial articular cavities for the coracoids
such as only occur in birds. The inter-coracoid process of the sternum
is compared with that of Bats, Birds, and Crocodiles.
The mechanism of the framework of the wings is said to be much
more bird-like than bat-like, the anchylosed scapula and coracoid
being remarkably similar to those of a bird of flight. The coracoid
is shorter and straighter in birds than in Pterodactyles, but no
comparisons are made with reptiles.
The humerus is known only by the proximal end. It is said to conform
at its proximal end more with the Crocodilian than with the Avian
type, but to have the radial crest much more developed than in either
Crocodile or Bird. The bone is, however, chiefly compared with
birds, and is figured between corresponding bones of a Vulture and a
Crocodile. The pneumatic texture is said to be as well marked as in any
bird of flight.
Of the carpus it is said, the Pterodactyle, in the complete separation
of the metacarpus from the antibrachium by two successive carpals
answering to the two rows, adheres more closely to the reptilian type
than to that of birds. But the row which was regarded as proximal is
the distal row, while the supposed distal row is proximal.
The claw-phalange and distal end of the wing-metacarpal, the mandible,
teeth, and jaw are the other bones described, but their comparative
osteology is not discussed. In the Professor's account of a fragment of
a jaw it is said, "The evidence of the large and obviously pneumatic
vacuities now filled with matrix, and the demonstrable thin layer of
compact bone forming their outer wall, permit no reasonable doubt
as to the Pterosaurian nature of this fossil. All other parts of
the flying reptile being in proportion, it must have appeared with
outstretched pinions like the soaring Roc of Arabian romance, but with
the demoniacal features of the leathern wings with crooked claws, and
of the gaping mouth with threatening teeth, superinduced."
When the specimens on which Prof. Owen had founded the foregoing views
of the osteology and classification of these animals were at length
returned to the Woodwardian Museum, it became a duty of the present
writer to arrange and name them. And in a Memoir on Pterodactyles which
was communicated to the Cambridge Philosophical Society and read March
7 and May 2 and 16, 1864, a position was claimed for them, distinct
from reptiles, as a separate sub-class of Sauropsida, nearly related to
birds.
In September of the same year a communication was made to the British
Association "On the Pterodactyle as evidence of a new sub-class of
vertebrata (Sauromia)," with enlarged drawings of the skull and some
of the other bones, in which the conclusions arrived at were that,
excepting the teeth, there is little in such parts of the head as are
preserved to distinguish the Cambridge Pterodactyles from birds; and
that the remainder of the skeleton gives a general support to the
inference from the skull.
Papers were communicated to the Cambridge Philosophical Society
on February 17, 1868, on indications of Mammalian affinities in
Pterodactyles in the pelvis and femur, and February 22, 1869, on the
bird-like characters of the brain and metatarsus in the Pterodactyls
from the Cambridge Greensand. The other references to Cambridge
specimens are in a paper "On the literature of English Pterodactyles"
in the _Annals and Magazine of Natural History_ for Feb. 1865, and in
"An epitome of the evidence that Pterodactyles are not reptiles, but
a new sub-class of vertebrate animals allied to birds," in the same
magazine for May, 1866.
In the meantime Prof. Owen's views have somewhat changed. In the first
volume of the _Comparative Anatomy and Physiology of the Vertebrata_
(1866), the Pterosauria are classed as the highest group of reptiles,
and take rank above the Dinosauria. In the second volume of that work
(1866), occurs the following passage:
"Derivatively the class of birds is most closely connected with the
Pterosaurian order of cold-blooded air-breathers. In equivalency it is
comparable rather with such a group than with the Reptilia in totality,
or with the Mammalia."
Organization.
Nearly every writer on Pterodactyles, who has expressed any opinion
at all, has formed an estimate of his own of their organization. They
have been assigned to almost all possible positions in the vertebrate
province, by great anatomists who all had before them very similar
materials. An account of these views is given by von Meyer in his
monograph of the Pterodactyles of the Lithographic Slate. It will not
be necessary to discuss these conclusions here, for the materials
from the Lithographic Slate and those from the Cambridge Greensand
are so different that no light would be thrown on the organization of
the animals by an exposition of any fallacious inferences from German
specimens. In England they are classed with Reptilia, chiefly through
the influence of the discourse upon them given by Baron Cuvier in his
_Ossemens Fossiles_[A]. It therefore may conduce to a clear view of
the subject to quote in Cuvier's words the passages in that memoir
which have been supposed to establish their position among reptiles. He
says,--"Ayant encore porté mon attention sur le petit os cylindrique
marqué _g_ (i.e. os quadratum) qui va du crâne à l'articulation des
mâchoires, je me crus muni de tout ce qui étoit nécessaire pour classer
ostéologiquement notre animal parmi les reptiles." The exact relations
of the quadrate bone are not seen in either Cuvier's or Goldfuss' or
von Meyer's figures of this Pterodactyle, the P. longirostris; but in
von Meyer's figures of P. crassirostris, P. longicollum, and P. Kochi
it appears to be a free bone articulated to the squamosal and petrosal
region of the skull and with the lower jaw. This is not the case with
either Chelonians or Crocodiles, which have the quadrate bone firmly
packed in the skull; nor is it paralleled even among those lizards
and serpents which have the bone as free; while, on the contrary, it
is characteristic of the whole class of birds. The form of the bone
is not more Lacertian than Avian, while its direct attachment to the
bone of the brain-case finds no parallel among lizards, but is exactly
paralleled in all birds.
[Footnote A: Tome V. Part a, pp. 358, 383. Edition, 1814.]
Cuvier then goes on to say, "Ce n'étoit pas non plus un oiseau,
quoiqu'il eût été rapporté aux oiseaux palmipèdes par un grand
naturaliste[B]." Which position he supports as follows:--
[Footnote B: Blumenbach.]
(1) "Un oiseau auroit des côtes plus larges, et munies chacune d'une
apophyse récurrente[C]; son metatarse n'auroit formé qu'un seul os,
et n'auroit pas été composé d'autanut d'os qu'il a de doigts." These,
though they may not be characters which are those of birds, are
certainly not eminently reptilian. The elongated form of the tarsals
in birds is peculiar, but quite functional, as may be seen among the
Penguins, where, when the so-called tarso-metatarsal bone is no longer
erect, it becomes much shorter, and is nearly separated into three
distinct bones. The cretaceous Pterodactyles appear to have this bone
exactly like that of birds.
[Footnote C: This shown in other specimens since figured, and in the
specimen from Stonesfield in the Oxford Museum.]
(2) "Son aile n'auroit eu que trois divisions après l'avantbras, et non
pas cinq comme celle-ce." This is a difference, but a difference of
detail only, and not a reptilian character. The creatures have wings;
and no reptile known, from recent or fossil specimens, has wings. The
general plan of the wing, though very unlike, approximates to that of
a bird. Most birds have two phalanges in the long finger, though some
have three. One Pterodactyle is described as having only two phalanges
in the wing-finger, while most of the German specimens appear to have
four phalanges. In birds the longest finger appears to be the middle
one, while in Pterodactyles it is the innermost one.
(3) "Son bassin auroit eu une toute autre étendue et sa queue
osseuse un toute autre forme; elle seroit élargie, et non pas grêle
et conique." The pelvis of Pterodactyle is not reptilian, and no
living reptile has a pelvis like it. It is not unlike the pelvis of
a Monotreme, but the ilium is more Avian. It resembles the pelvis
of Dicynodon. And the discovery of a long-tailed bird-like the
Archæopteryx shows that the tail is like that of old birds, even if
it also presents some analogy in form to that of certain reptiles and
mammals.
(4) "Il n'y auroit pas eu de dents au bec; les dents des _harles_ ne
tiennent qu'à l'enveloppe cornée, et non à la charpente osseuse." This
is not a reptilian character. Among reptiles some tribes have teeth,
others want them; and among mammals some animals are without teeth,
though they are so characteristic of the class. It is an anomaly that
birds should all be toothless. And so, without citing the supposed
teeth of _Archæopteryx_, it may be affirmed that it would be no more
remarkable for some birds to have teeth than it is for some mammals and
reptiles to be without them.
(5) "Les vertèbres du cou auroient été plus nombreuses. Aucun
oiseau n'en a moins de neuf; les palmipèdes, en particulier, en ont
depuis douze jusqu'à vingt-trois, et l'on n'en voit ici que six ou
tout au plus sept." This is a variation of detail such as, had it
occurred among birds, would hardly have been deemed evidence of their
affinities. When the variation of the neck-vertebræ ranges from 23 to
9, the further reduction of the number to 7 becomes insignificant, and
does not show that the animal was a reptile.
(6) "Au contraire, les vertèbres du dos l'auroient été beau-coup moins.
Il semble qu'il y en ait plus de vingt, et les oiseaux en ont de sept
à dix, ou tout au plus onze." This modification is obviously the
result of smaller development of the pelvic bones from front to back,
and hence of the small number of vertebræ in the sacrum. It does not
support the reference of Pterodactyles to the class of reptiles.
Speaking of the teeth, it is said, "Elles sont toutes simples,
coniques, et à peu près semblables entre elles comme dans les
crocodiles, les monitors, et d'autres lézards." The teeth of
Pterodactyles are (in the skull) for the most part in the premaxillary
bones, in which it is so characteristic for the teeth of animals to, be
merely conical and simple. Therefore it would have been difficult to
imagine the teeth to have been anything but what they are, whatever the
affinities of the Pterodactyle might be.
It is remarked, "La longueur du cou est proportionée à celle de la
téte. On y voit cinq vertèbres grandes et prismatiques comme celles des
oiseaux à long cou, et une plus petite se montre à chaque extrémité."
This adds nothing to the evidence for its reptilian character.
"Ce qui est le plus fait pour étonner, c'est que cette longue téte
et ce long cou soient portés sur un si petit corps; les oiseaux
seuls offrent de semblable proportions, et sans doute c'est, avec la
longueur du grand doigt, ce qui avoit determiné quelques naturalistes
à rapporter notre animal à cette classe." Nor is this evidence that
the animal was a reptile. And in many minor matters Cuvier is careful
to show how their modifications resemble those of birds; and when
this is not so, birds are the only animals from which he finds them
varying. And the few suggestions which are thrown out respecting their
affinities with lizards are upon points which are also common to birds.
Thus what Cuvier did was to distinguish these animals from birds, and
incidentally to show that their organization was a modification of
that of the Avian class. And the legitimate inference would have been
that their systematic place was near the birds, and not that they were
reptiles.
But in Germany Cuvier's views on Pterodactyles have by no means been
submissively received; and great anatomists, since he wrote, have
propounded and defended views as various as those of the anatomists
who preceded him, and with no less confidence in the results of their
science. In the brief space at my command it would be impossible to
do justice to the works of this array of philosophers, and therefore
I present in a somewhat condensed version the epitome of their
conclusions given by Hermann von Meyer in his _Reptilien aus dem
Lithographischen Schiefer der Jura_. They form a commentary on the
casts of Solenhofen Pterodactyles contained in the Woodwardian Museum.
Sömmerring
regarded the Pterodactyle as an unknown kind of bat, and thought that
Cuvier was misled by Collini's imperfect description. He believed that
he found in them different kinds of teeth as in mammals; and regarded
them as differing from bats chiefly in having larger eye-holes, a
longer neck, four fingers and four toes, a longer metatarsus, and in
having but one elongated finger; and found the closest analogue of the
fingers in Pteropus marginatus of Bengal. And although inclined to
place the Pterodactyle between Pteropus and Galeopithecus, he suspects
from the bird-like characters of the head and feet that its true place
is intermediate between mammals and birds.
Oken[D].
[Footnote D: _Isis_, 1818, p. 551.]
Oken reasoned carefully so far as his materials went. He dwells much
on the analogy of the wing to that of a bat, and seems to suspect that
the marsupial bones would hereafter be found; and, excepting the head,
finds that the other parts of the skeleton have their corresponding
bones among mammals.
Afterwards, when he saw the specimens at Munich, he was so much struck
at finding the quadrate bone of Lacertian form, though Sömmerring
could not detect it even with a microscope, that he is shaken in his
mammalian faith, and inclines to consider the animal a reptile.
Wagler[E].
[Footnote E: _System der Amphibien_, 1830, p. 75.]
Wagler was impressed with the resemblance of the jaws and the rounded
back part of the skull to those of Dolphins, and so far as the head
went conceives it to have had nothing in common with Lizards. He
recognizes mammalian characters in the pelvis and sternum, and fails,
like Sömmerring, to detect a quadrate bone, and finds the sum of the
characters like those of other extinct animals, such as Ichthyosaurus
and Plesiosaurus, suggesting for it a position between mammals and
birds. He supposed it unable to fly, that it never left the water,
but swam about on the surface like a swan, and sought its food on
the sea-bottom. He imagined the long arms to have been used after
the fashion of turtles and penguins to row the body along; while to
the claws he attributes the function of holding the females in the
generative process.
Goldfuss[F].
[Footnote F: _Nova Acta Acad. Leopold._, 1831, Vol. XV. Pt. I. p. 103.]
sees in Pterodactyle an indication of the course that nature took in
changing the reptilian organization to that of birds and mammals. The
less important organs, those of motion, assimilate partly to those
of the bird and partly to those of the bats, but always preserve
the fundament reptile type and reptile number of bones. The skull,
fluctuating in character between the monitor and crocodile, hides its
reptile nature under the outer form of the bird, but retains the teeth.
To change the skull into a bird's skull it would only be necessary that
a few separate elements should be blended together, and that a few
peculiar bones should be removed. The length of the neck, varying only
in a few species, is a deviation from the reptile type, and indicates
an approximation to the structure of 'the bird; but the number of
the vertebræ remains constant notwithstanding the increased length.
The fundamental plan of the crocodile may be recognised in all the
important parts of the vertebræ. The body of the reptile, to be enabled
to fly, would need a larger breast and a stronger structure of the
fore-limbs. The shoulder-blade of the reptile, with its extremities
forming the glenoid cavity, is necessarily smaller and prolonged
backward, and altered to resemble that of a bird. The scapula only
formed the back part of the glenoid cavity, but it is thick and strong,
suggesting an affinity with the bats.
The breast-bone, in the form of a shield, is changing into that of a
bird; as are the ribs, which are attached in a peculiar way to the
vertebral column. It is really the strong sternum of the Chameleon,
with moveable dorsal vertebræ. The whole chest is supported by the
peculiar continuation of the wings of the pubic bones (Schambein).
The ischiac and pubic bones resemble those of the Chameleon, but the
ilium runs a little down, like that of a bird, and is only slightly
connected with two sacral vertebræ, as in reptiles, prolonging itself
a little upward and forward, as in mammals. The wings of the pubic
bones exist in the Turtle and Monitor, but of small extent; they are
also represented in the mammals by the upward development of the pubic
bones in those families, genera, and species, in which nature has
indicated by variety of shape, or peculiarities of development, or by
affinities with reptiles, quite a new type and capacity for variation
within certain limits, which is especially the case with certain
Rodents and Opossums, and Monotremes. It would not be astonishing to
find in Pterodactyles the marsupial bones. And indeed the Pterodactylus
crassirostris has a small tongue-shaped bone, probably belonging to the
pelvis. The less important part of the skeleton, the tail, is formed
precisely as in mammals, and is identical with that of the bats. Both
the thigh and shin are mammalian, and only the foot retains the same
number of parts as in reptiles.
This animal was enabled by means of the pelvic bones and the long
hind-legs to sit like the squirrels.
We should regard this position as natural but for the long wing-finger
hanging far down the sides. If it were to creep along it would have
the same difficulties as a bat, and the length and weight of the
head, as well as the proportional weakness of the bind limb, make it
improbable that they progressed by leaping. These animals made use of
their claws only to hang on to rocks and trees and to climb up steep
cliffs. They could fly with their wings, and keep themselves aloft in
order to catch insects or sea animals. The wide throat and the weak
and high supports of the jaw-bone make it probable that they only used
their teeth to capture their prey and not to mince it. By means of
their long neck, which they usually bore curved backward in order to
keep their balance, they could stretch out their head to their prey
and change their centre of gravity, and so fly in different positions.
The fundamental type of the Crocodile and Monitor leads us to suspect
that they had a skin covered with scales. The approximation to the
shape of the Bird makes it probable that they were feathered. And the
whole outline, similar to that of the Bat, leads to the supposition
that they were covered with hair, like the Monotremes. Goldfuss thinks
he has got a clear insight into the covering of the body and the whole
condition of the wing in examining the Pt. crassirostris. And the soft
state of the stone near the bones he attributes to the presence of
the soft parts of the animal; and supposes that on the original folds
of the wing-membrane are to be seen tufts and bunches of curved hair
directed downward and sideway[G]. And on the principal slab he finds
evidence that the Pterodactyle had a mane on the neck like a horse.
The tufts on the counter slab have some similarity with the feathers
of the ostrich. Some very tender impressions on both plates still more
resemble feathers. He recognizes the outline and faint diverging rays
of a bird's feather, but never sees a strong quill. The microscope,
instead of making the image clearer, makes it, on the contrary, vanish,
because then the rough parts become prominent. Also on the slab which
contains the Pterodactylus medius[H], are seen numerous lines and
fibres diverging like a bird's feathers. And on the upper part of the
belly is the appearance of a scanty texture of hairs and feathers. The
visible marks of two cylinders of the thickness of a quill, made of
thin substance and filled with limestone, he would regard as quills if
there were clearer marks of their feathers to be seen. As a note upon
this von Meyer says, after examining the slabs, that the particles
considered by Goldfuss to be hairs and feathers rest upon appearances
not only to be seen in the vicinity of Pterodactyles, but which occur
upon many other kinds of petrifactions that have nothing in common with
the Pterodactyle; and that the roughnesses of the slab have nothing to
do with the folds of the wing or the muscles.
[Footnote G: This is represented in Pl. 7, 8 of his memoir, _loc. cit._]
[Footnote H: Pl. 6, _Nova Afta Acad. Leopold_, Vol. XV. Pt. 1.]
Wagner[I]
[Footnote I: _Abhandl. Bayerischen Acad._ 1852, Vol. VI.]
is so convinced that the Pterodactyles are Amphibians approximating
to the Saurians, that he does not think it necessary to go into
any controversy in the matter; but he acknowledges that their
forms sometimes present peculiarities of bird and mammal. The head
especially shows a blending of the bird and reptile types. Its outline,
particularly when seen from above, is that of a long-beaked water-bird.
And the long interval between the nose-holes and the tip of the jaw,
and the peculiar fact of a hole between the nose and eye-holes, and
the want of the continuation of the coronoid of the lower jaw, rather
resemble a water-bird than a Saurian. But the presence and the form
of the teeth show it to be a Saurian; and not only the teeth, but the
configuration of the whole back part of the skull, reproduces the type
of the Monitor. The sclerotic circle is a peculiar mark of birds and
saurians. Very peculiar, however, is the extremely short back part
of the skull; and the articulation of the lower jaw, stretched far
forward and united just under the middle of the eye-hole. The more
or less long neck, which may assume the form of an S, deviates very
much from the short stiff neck of reptiles, and is quite bird-like,
the neck-vertebræ of which those of the Pterodactyle closely resemble
in shape; while their constant number of seven reminds us of mammals
and crocodiles. The neck has the same flexibility as in a bird. The
short and weak trunk-vertebræ are in such disproportion to the length
and strength of the neck-vertebræ as is never met with even in the
birds and mammals which have the longest necks. The trunk-vertebræ
are completely separated from each other, and may be divided into
dorsal, lumbar, and sacral vertebræ. The transverse processes of the
back-vertebræ are notched out like those of the crocodile. The tail
is short in most species, and this is a deviation from the type of
the Saurians, and an approximation to birds and to many mammals. But
there are some kinds with very long tails, as is the case with mammals
and usually with Saurians. But the vertebræ of these long-tailed
Pterodactyles deviate very much from those of Saurians. And while
the Saurian vertebræ are provided with long transverse processes and
upper and lower spinous-processes (Dorn-Fortsätzen), they seem in
the Pterodactyle to be almost devoid of processes and resemble those
of mammals, on the tails of which these processes soon disappear.
In a certain point of view we could say of the vertebral column of
the Pterodactyle, that it has borrowed the neck from the bird, the
trunk from the reptile, and the tail from the mammal. The ribs are
connected to the transverse processes as in crocodiles, except with the
atlas and axis. Quite in the type of the Saurians are the abdominal
ribs, which are wanting to all birds and mammals, but often occur in
the Lacertian order. The structure of the shoulder and breast-bone
separate the Pterodactyle from the mammal, these parts being formed
after the type of the Birds and Saurians, the characters of which are
blended together. The small and elongated shoulder-blade, like the
coracoid bone, belongs to the type of the bird rather than to that
of the Saurians, of which, in reference to the last-named bone, only
crocodiles have a similar one. The breast-bone, by its large expansion,
points to the crocodiles, but at the same time, by the want of the
keel, points to the ostrich-like birds, save that it is proportionally
larger and wider than in these. The Pterodactyle, in common with the
crocodile, wants the patella. The pelvis is formed on the type of the
Saurians, although the ilium, by length and form, points somewhat to
the mammals. The length and delicate form of the long bones of the
limb, as well as the larger development of the fore-arm than of the
upper-arm, and larger development of the lower thigh than of the upper
thigh, and the thinness and elegance and shortness of the ?fibula
(Wadenbein) have the characters of birds. The length of the middle hand
[metacarpals] resembles that of birds, but its form in Pterodactyle
is conformable to that of mammals. The first three fingers have the
form and condition of the phalanges of lizards. The phalanges form the
series 2, 3, and 4. The fourth, or air-finger, on the contrary, is
of a peculiar type, of which no analogue is found in other animals,
unless a somewhat similar arrangement be accredited to the bats. It
is of enormous length, composed of four parts and without a claw.
The hind-leg is, in proportion to the fore-leg, weak, and in general
does not take the bird-form, but that of a Saurian. It has five toes,
with unusual arrangement of the phalanges into the series 1, 5, 4,
3, 2. One toe has no nail, and the others have claws weaker than
those of the hand. It can hardly be supposed that the animal lived
in the water. All Saurians that live either in the water or on land
are short-legged; it is the same with the swimming birds. But the
Pterodactyle has its hind-legs as long as a land or air-bird; and as in
these, the shin especially exceeds the length of the thigh. At the same
time the toes, when they are in their natural position, were so close
together that we may suppose the animal not to have been web-footed.
The great development of the hand, by means of the long middle hand
and especially of the enormous length of the air-finger, makes it
probable that it was the chief organ of flight, as in birds and bats;
also deviating in a peculiar manner from both these types, the long
air-finger served to expand the wing-membrane, which extended from the
upper part of the finger to the trunk, and which in all probability
did not touch the hind-legs. This we infer from the circumstance that
the animal, in a position with the organs of flight folded up, was
not supported like the bat on its four feet, but stood upright on its
hind-legs like a bird. Such a position presumes the same freedom in
moving the hind extremities as with birds; only in such a position
could the animal walk on without being hindered by its flying organs
when they were folded up like those of a bird. Only in such an upright
position could the animal keep upright its unusually long head with the
long and strong neck and be kept in balance, the neck being able to
take a sigmoid curve like that of a bird.
Wagner concludes: "By these means we have recognised in the
Pterodactyle a Saurian, but of a habitude which greatly removes him
from all others of his kind, and approximates him to birds. Excepting
in ability to fly, he has nothing in common with the birds. The opinion
'that the animal is half crocodile half monitor disguised as a bird,
but intending to be a bird,' is therefore not only a paradox but also
false. With more truth, but less phantasy, we could say that the
Pterodactyle was a Saurian in transition to the Birds."
Quenstedt[J].
[Footnote J: _Ueber Pterodactylus Suevicus._ Tubingen 1855.
In the long thigh, with the long neck, Quenstedt sees evidence that the
animal was able to walk upright, being probably still more upright than
birds, since the great disproportion between the neck on the one hand,
and the thigh on the other, could not have allowed a more appropriate
position. At the same time he makes a question, Did it go on four feet?
But a little later, in his book, _Sonst und Jetzt_, 1856, he gives
a sketch of the animal resting on its four legs; and remarks, "The
position upon four feet is however hypothetical, but is probable. It
had its wings folded back. The slightly curved and thin bones of the
middle hand probably served to support the flying-membrane, and had
therefore the same function as the spur-bone in the bats." Finally, he
says in his book, _der Jura_, p. 813, "Perhaps this animal walked from
time to time on four legs, being then supported by the fore-end of the
metatarsal bone."]
Burmeister[K].
[Footnote K: _Beleuchtung uniger Pterodactylus arten._ 1855.]
entirely rejects Quenstedt's opinions with regard to their upright
position. He makes the following remarks: 'The animal walked on the
free fore-toes and bore the wings like a bat, though with the body not
in an upright position like a bird, but four-footed. The hind-foot is
much too small for such an upright position, and the fore-foot much too
strongly developed. I therefore believe that the Pterodactyle could
much better have walked four-footed than a bat, because it possessed so
much better developed fore-feet.' In the length of the tibia Burmeister
sees no reason for the upright position, but, as he says, only a means
for the wide expansion of the flying-membrane;--and an endeavour in
walking on four feet to bring the leg into the necessary harmony with
the arm, which is so much elongated with the flat-hand.
Hermann von Meyer[L].
[Footnote L: _Fauna der Vorwelt. Reptilien aus dem Lithographischen
schiefer._ Frankfurt am Main. 1859. pp. 15-23.]
The skull of the Pterodactyle can only be compared with those of
birds and lizards. The form is essentially Avian, and the sutures are
indistinct or obliterated as in birds, while in reptiles they are
persistent The temporal bone enters into the formation of the reservoir
for the brain, which is eminently characteristic of birds and quite
different from anything found in lizards. The snout resembles a bird in
being chiefly formed by the intermaxillary bone, which bounds the front
of the anterior nares; and, as in birds, the bone extends backward
between the eye-cavities to the frontal bone. The corresponding
intermaxillary ridge of the Monitor is of less extent.
The frontal-bone forms the highest part of the skull, and is similar
to that of birds. The principal frontal is double, and forms the upper
and hind part of the cavity for the eye, and covered the greater part
of the large brain, composed of two hemispheres, in which Oken long
ago saw a similarity to the higher animals. The arched form of the
back part of the skull is bird-like. The double parietal adjoins the
principal frontal, and is conditioned like the parietal in birds. The
supra-occipital is single as in birds, expanded, and forms the part of
the skull which extends furthest back. From the form of the back part
of the skull it may be concluded that the foramen magnum was situated
as in birds, and that the head and neck were moved as in birds, and not
as in reptiles and mammals.
The temporal bone rests upon the parietal and frontal, and forms much
of the temporal foss. Its anterior border does not appear to enter
into the margin of the orbital cavity as in birds, but seems to be
replaced by the post-frontal, which resembles that of the Chameleon.
Its hindmost branch, which can hardly be supposed to be the jugal,
forms the outer boundary of the temporal foss by uniting with a process
which is probably part of the mastoid. A similar closing of the cavity
for the temporal muscles is also to be found in birds. The jugal
and maxillary do not follow the bird type. The jugal consists of a
single bone which forms the greater part of the anterior and inferior
boundary of the cavity of the eye, which is surrounded with bones, as
in Dragons and Iguana. In those birds in which the cavity of the eye is
surrounded with bones the jugal does not enter into it. As in lizards,
at its upper end the jugal is commonly connected with the lachrymal,
which bone is like that of a bird. A bone, which appears to be the
pre-frontal, enters into the back of the nasal aperture.
The nostril is double and often of large size.
The perforation in the skull between the orbit and nares is bird-like.