* * * * *
These authors further point out that the vomers appear for a small space
in the posterior part of the palate, that the opercular or splenial
bones join in the symphysis of the lower jaw, and that the cervical and
dorsal scutes form one continuous shield; and they represent the two
anterior mandibular teeth passing in grooves on either side of the end
of the premaxilla. In fact, they fully and completely establish the fact
that their new species belongs to the _Longirostres_ of Cuvier, or to
the Gavials of later writers.
Under these circumstances, it is somewhat surprising to find the
deliberate conclusions of these careful investigators set aside in the
following brief passage:--
"This Bornean species (_C. Schlegelii_) was, in fact, originally
described as a new species of Gavial; but the nasal bones, as in the
fossil from Sheppey, figured in t. ii. 15, extend to the hinder
border of the external nostril."--_Owen_, _Fossil Reptilia of the
London Clay, Crocodilia_, p. 15: 1850.
Müller and Schlegel give remarkably clear and beautiful figures of the
skull of their Gavial; and these show at once that the nasal bones do
not "reach the hinder border of the external nostril," but meet the
premaxillaries at a point very distant from that border, viz. opposite
the ninth tooth. Even did the nasal bones reach the posterior boundary
of the nostril, such a character would not outweigh those derived from
the relations and number of the teeth, the structure and extent of the
mandibular symphysis, and the disposition of the dermal scutes,--all of
which are so clearly and definitely set forth by Müller and Schlegel,
that it seems difficult to understand how any one who had consulted the
original memoir could have overlooked them.
It was possible, however, that Müller and Schlegel, notwithstanding
their great opportunities, might have erred in their statements; and I
therefore gladly seized the opportunity of testing their description by
comparing it with an authentic skull of the species in question, from
New Guinea, in the collection of the British Museum.
I have found the statement of Müller and Schlegel minutely accurate
in almost all points; and there cannot be the slightest doubt, not
only that the Schlegelian crocodile is one of the _Gavialidæ_, but
that it forms a distinct generic type in that family, as different
from _Gavialis_ as _Caiman_ is from _Jacare_, or _Mecistops_ from
_Crocodilus_.
* * * * *
The following are the most important measurements of the skull of
_Rhynchosuchus Schlegelii_ in the British Museum collection:--
Inches.
Length from the end of the premaxilla to that of
os quadratum 23
Breadth from outer edge of one os quadratum to that
of the other 8-3/4
Breadth across the face in front of the orbits 4
" at the 9th tooth 2
" at the 5th tooth 1-1/2
" at the 3rd tooth 1-3/4
" of the beak-like curved process which carries
the two anterior teeth 1
Mean width of lower jaw from symphysis to extremity 1-5/8
Length 12
No tooth measures transversely more than 3/16
The face is very smooth; but a slight longitudinal groove runs down on
each side from the anterior margin of the orbit for about two inches.
Anteriorly to this point the snout retains a nearly even diameter as
far as the ninth tooth, in front of which it suddenly narrows a little,
retaining nearly the same dimensions to the fourth tooth, where it
widens a very little, and then suddenly narrows to the terminal beak.
The lower jaw does not expand at all at its extremity. The nasals join
the premaxillaries opposite the ninth tooth, and the splenial bones, in
the lower jaw, end opposite the tenth mandibular tooth, as the figures
of Müller and Schlegel show. The vomers appear between the inner edges
of the palatines posteriorly, as a thin bony band 1-3/8 inch long
by 1/8 inch wide, which tapers at each end and is divided by a
longitudinal suture. The ninth tooth of the upper jaw is stronger than
the rest.
The only point in which the description of Müller and Schlegel seems
to me to be incomplete[7] is with regard to the disposition of the
teeth. They say--"The teeth of _C. Schlegelii_, as regards their form
and development, more nearly resemble those of the true Crocodiles;
but in the way in which the teeth of the two jaws are opposed, there
is the most complete resemblance between our species and the Gangetic
Gavial,--both which species differ from all other crocodiles in the
circumstance that when the mouth is shut, all the teeth of the under jaw
project outside the lateral margin of the upper jaw" (_l. c._ p. 22).
What I find is this:--The anterior teeth of both the upper jaw and
the mandible are long, slender, sharp-edged, and slightly curved. The
posterior eleven, on each side, in the upper jaw, are short, straight,
conical, and constricted below their crowns. There are deep interdental
pits between the ten posterior mandibular teeth, into which the opposed
teeth of the maxilla are received when the jaws are closed. All the
mandibular teeth, except the two anterior and the fourth pair, pass into
like pits in the upper jaw. The anterior eight teeth on each side of
the upper jaw pass straight down outside the lower jaw. In the Gangetic
Gavial the relations of the teeth of the two jaws appear to me, as I
shall state below, to be very different.
_Rhynchosuchus Schlegelii_ inhabits the inland lakes of Borneo, and is
found in New Guinea.
[7] Or it is possible that the _Rhynchosuchus_ from New Guinea,
which I have examined, is specifically distinct from the Bornean
form.
Genus 7. GAVIALIS.
There are twenty-seven or twenty-eight teeth in the upper, and
twenty-five or twenty-six in the lower jaw. The mandibular symphysis
extends to the twenty-third or twenty-fourth tooth. The lateral teeth
of both jaws are, all but the very hindmost, directed obliquely
downwards (or upwards), forwards or outwards, and are not received
into interdental pits. The anterior margins of the orbits are raised.
The premaxillæ and the end of the mandible are greatly expanded. The
premaxillo-maxillary suture reaches the level of the fourth tooth behind
the canine notch.
The only true _Gavialis_ is the well-known _G. Gangeticus_ from the
East Indies. In this 'Gavial,' or 'Garrhial,' the vomers are slender
bones which do not extend further forwards than the level of the
twenty-second or twenty-first tooth, and have but a very short and
slender representative of the anterior flattened division of the bone in
_Jacare_; posteriorly they extend back to the level of the descending
processes of the prefrontals. In a skull 25 inches long the vomers
have a length of about 4 inches, extending as they do a little further
forward than the palato-maxillary suture. The median nares are opposite
the twenty-fifth tooth.
* * * * *
All the _Crocodilia_ which I have enumerated are provided with two
perfectly distinct kinds of dermal armour,--the one consisting of
plates of horn, produced by a modification of the superficial layer of
the epidermis; the other composed of discs of bone marked by a peculiar
pitted sculpture on their outer surfaces, and developed within the
substance of the dermis. To the former I shall apply the term "scales;"
the latter are what I have denominated "scutes."
All recent _Crocodilia_ have both scales and scutes in the dorsal
region of the body, the scutes underlying, and having the same general
form as the scales. In all, the ventral region of the body is also
covered with scales which have a very definite shape; but in no recent
Crocodilian which I have examined, save those species which are
included in the genera _Caiman_ and _Jacare_, are there any scutes in
the ventral region.
Again, in the genera _Alligator_, _Crocodilus_, _Mecistops_,
Rhynchosuchus, and _Gavialis_, the edges of the scutes, except those of
the two median longitudinal rows, are hardly ever united by sutures,
nor do the posterior margins of those in each transverse row overlap the
anterior margins of the succeeding row. At any rate, there is no flat,
bevelled, articular facet on the outer surface of the anterior margin of
a scute, for articulation with the inner surface of the posterior margin
of its predecessor. In the genera _Caiman_ and _Jacare_, however, the
lateral edges of all the scutes of the dorsal and ventral shields are
united by serrated sutures; and the anterior end of the outer face of
each is provided with a well-marked smooth facet, which is overlapped by
the smooth under-surface of the scute in front of it.
I first noticed the remarkable structure of the dermal armour of these
_Alligatoridæ_ in the skin of a _Jacare_ (_sp. incerta_), wanting the
end of the tail, but which must have belonged to an animal between five
and six feet in length. It had long been in my possession; but I had
never before had occasion to study its characters minutely.
The horny scales, which had the appearance of thin tortoise-shell,
could be readily peeled off (especially by the aid of a little caustic
potash); and then the white surface of the subjacent bony scute upon
which they were modelled came into view. It is to be understood,
however, that the inner surface of the scale corresponded only in its
general form with the outer surface of the scute; for it did not dip
into the pits with which the latter is sculptured. These are in fact
filled by the dry dermis which extends over and encloses the scute, a
very thin layer (bearing the rete mucosum) being interposed between it
and the scale; so that the pitted sculpture does not come out well until
the scutes have been boiled.
The _dorsal_ scutes are both carinated and angulated. By the application
of the former term, I mean to indicate that, along a median or submedian
longitudinal line, their substance is more or less elevated, so as, in
many cases, to form a very prominent crest. This crest always subsides
before it reaches the anterior margin of the scute, though it may extend
beyond the posterior margin. Its highest point is always behind the
centre of the scute, and is devoid of sculpture. The sculpture however
seems to radiate from this point, inasmuch as it consists, on the
greater part of the scute, of distinct pits, which are usually round
towards the centre, but towards the periphery become ovals with their
long axes directed towards the point in question.
The smooth inner surfaces of the scute shelve towards a depression
which corresponds with the external ridge, under which the sides of
the scute seem to meet in an angle. This may be called the 'angulation'
of the scute. From before backwards, the inner surface of the scute is
a little convex. The scute is thickest in the middle; posteriorly, it
thins off to an edge and overlaps its successor; anteriorly, its outer
surface is bevelled off at an acute angle with the inner, so as to give
rise to a smooth shelving surface--wide from side to side, narrow from
before backwards--forming the 'articular facet,' which is overlapped by
the inner surface of the posterior edge of the preceding scute. I have
termed this the 'articular facet;' but it must not be supposed that
there is anything like a true joint between the opposed facets of the
overlapping and overlapped scutes; on the contrary, they are at once
separated and connected by the dermal connective tissue.
The posterior margin of the articular facet is separated by a deep
transverse groove, divided by little partitions into as many pits,
from the rest of the sculptured surface; but there is no trace of any
suture dividing the scute into two portions. The lateral margins of each
scute are united by serrated sutural edges with those which lie next to
them in the same transverse row; so that each row forms a nearly solid
flat bony bar, composed, in the middle of the back, of as many as ten
distinct scutes. The outer edges of the outermost scutes only, thin off
and exhibit no sutural serration, inasmuch as they are not directly
connected with ANY other scutes.
The median line of the back corresponds in general with the suture
between the two middle scutes of each transverse row; so that the scutes
are disposed symmetrically on either side of that line. Furthermore,
the anterior part of the inner surface of each of the two middle scutes
is connected by ligament with the extremity of the spinous process of a
vertebra; at least, this is the case in the dorsal, lumbar, sacral, and
anterior caudal regions.
The scutes which protect the _ventral_ side of the body, from the
throat backwards, are four-sided and similar in their ornamentation
to the dorsal scutes; but they exhibit neither ridge nor angulation,
their outer and inner surfaces being parallel, and either nearly flat
or evenly curved. Each forms, in fact, a segment of a large cylinder,
inasmuch as the whole ventral shield is convex transversely, being
nearly flat in the middle and much bent up at the sides. The dorsal
shield, taken as a whole, is, on the contrary, nearly flat. The lateral
edges of the ventral scutes interlock suturally; and their anterior and
posterior edges are overlapped and overlap, just like the dorsal scutes.
The outer edges of the outermost ventral scutes thin off and are not
united with any bony element; and the ventral, like the dorsal scutes,
are usually arranged symmetrically on either side of the median sutural
line. There may be as many as twenty-two scutes united by their lateral
sutures into a single strong, curved, transverse, bony, bar-like segment
of the ventral armour.
Throughout the neck and body, and as far as the commencement of the
tail, the ends of the dorsal and ventral bony bars, whose sum may be
regarded as a dorsal and a ventral shield respectively, are separated
by an interval of integument, in which only small scattered scutes are
visible. The physiological import of this arrangement becomes obvious
when we consider in what manner the animal breathes; and indeed the
integumentary interval answers very precisely to the leather which
connects the two boards of a bellows. Again, though the limbs are
themselves covered with articulated scutes, they are afforded free
play upon the body by this flexible interspace. Immediately behind the
hind legs, the ventral and dorsal shields unite; and the tail is from
that point surrounded by a succession of bony hoops, each of which
corresponds with a vertebra, the segments of the exoskeleton answering
to those of the endoskeleton.
The most remarkable feature about the ventral scutes, however, and that
in which they differ most widely from the dorsal ones, consists in the
fact that each scute is composed of two distinct pieces, an anterior
and a posterior, which unite together by a transverse serrated suture.
The anterior piece or 'semi-scute' may attain to three-quarters the
length of the posterior, and it has exactly the same width. The anterior
semi-scute bears the articular facet and the transverse pitted groove,
whose posterior wall is just in front of its hinder edge, or in other
words, of the suture, when the two semi-scutes are united.
Such are the general characters and mode of arrangement of the dorsal
and ventral armour of _Jacare_. But there remain many noteworthy
peculiarities in the disposition and number of the components of each
band of the armour.
Thus, in the _dorsal shield_ there are two rows of nuchal scutes, each
containing eight separate keeled bony plates; and of cervical scutes
there are five rows, the two anterior of which contain four angulated
and carinated scutes each, while the three posterior contain only two
scutes each. All these scutes, except the anterior row, have articular
facets; and all those of each row are united suturally. Of dorsal scutes
there are thirty transverse rows up to the median keel of the tail,
which commences with the thirty-first row. The number of scutes in each
row is as follows:--
Rows. Scutes.
1, 2, 3, 4 6
5, 6, 7, 8, 9, 10, 11 10
12, 13 8
14, 15 6
16, 17, 18 4
19 6
20 8
23, 24 6
25, 26 5
27, 28 4
29, 30 4
31, 32, 33, 34 5
The rest of the tail is wanting.
Throughout the dorso-lumbar and sacral regions (_i. e._ up to the
nineteenth row), the median scutes are hardly keeled at all, while the
outer ones are the more strongly carinate the more external they lie.
In the caudal region, the second scute from the middle line, in the
twenty-third row, has a strong keel and angulation, which grows stronger
in the corresponding scutes up to the thirtieth inclusive, until the
superior and lateral faces of these scutes, in the twenty-ninth and
thirtieth rows, are inclined to one another at a right angle and
very strongly keeled. I have said that, as a rule, the median line
is occupied by a suture between two median scutes; but in the caudal
region[8], in the twenty-fifth row (which corresponds with the sixth
caudal vertebra) the two median scutes are replaced by one flat scute,
so that there is no suture in the middle line. In the twenty-sixth row
there is a similar arrangement, but the flat scute is smaller; and in
the twenty-seventh no trace of it is left, so that the strongly keeled
lateral scutes meet in the middle line, which is again occupied by a
suture. This continues up to the thirty-first row, when the median scute
reappears as a thin vertical plate, broader below and in front, where it
articulates with the median lateral scutes, than above and behind, where
it exhibits a free edge only covered by the horny epidermis. It is thus
that the serrated dorsal crest of the tail is formed. The scutes of the
crest exhibit only very small round and distant pits.
The _ventral shield_ begins in the neck just behind the level of the
anterior margins of the orbits: the fifteen anterior rows may be termed
subcervical, as they lie in front of the thorax. In the first six rows
the scutes are very small, and increase in number up to twelve in a row.
In the next six rows there are ten scutes in a row, and in the last
three, twelve. All these rows are symmetrically divided by the median
line. In the three hinder rows the inner scutes are longer than the
outer ones; and this is most markedly the case in the fifteenth row,
whose innermost scute is half as long again as the corresponding one of
the preceding row, and more than three times as long as the outermost of
its own row.
[8] The second and third cervical rows in _Caiman palpebrosus_ and
_trigonatus_ also contain a median scute, and consequently an odd
number of scutes. In _Caiman trigonatus_, the third to the ninth
supra-caudal rows have each a median single scute.
The sixteenth row differs from its predecessors and successors, and may
be termed the axillary row. It is bent upon itself with an angle open
forwards, and is divided into two halves (each of which contains seven
scutes) by the union of the middle scutes of the fifteenth subcervical
with those of the first row of what may be termed the subdorsal scutes,
or those which lie under the thorax and abdomen. Of subdorsal and
subcaudal scutes there are, up to the broken-off end of the tail,
thirty-seven rows, with the following numbers of scutes:--
Rows. Scutes.
1 12
2 10
3, 4, 5, 12
6, 7, 8, 9, 14
10 16
11 14
12-17 14
18-20 12
21 14
22 18
23 22
24 22
25 20
26-28 18
29-31 16
32-34 14
35 12
36, 37 10
It will be noticed that there are three more rows of ventral than of
dorsal scutes. On endeavouring to ascertain how this came about, I
observed that the first subdorsal was a good deal behind the first
dorsal row, though the eighth to the twelfth dorsal corresponded exactly
with the eighth to the twelfth ventral rows. In the anterior part of the
body, therefore, there is a clear general correspondence between the
segments of the dorsal and those of the ventral armour.
In the caudal region, again, I found that the twenty-fourth ventral
row, which is the first of the caudal rows not excavated by the vent,
corresponded exactly with the twenty-first dorsal row. It was clear,
therefore, that three ventral rows wore interpolated somewhere between
the twelfth and twenty-first dorsal rows; and on close examination I
found this interpolation to arise from the doubling of the fourteenth,
fifteenth, and sixteenth ventral rows.
I have examined _Jacare fissipes_ and _nigra_, _Caiman trigonatus_,
and _C. gibbiceps_, in the British Museum; and I find, in all, dorsal
and ventral armour having the same essential arrangement as that just
described. A specimen of _Caiman palpebrosus_ about two feet long, the
opportunity of examining which I owe to Dr. Grant, exhibits the dorsal
and ventral shields (whose scutes are in the main similarly arranged)
very beautifully; and a young _Jacare_ of about 18 inches in length,
for which I am indebted to the kindness of the same gentleman, proves
that the scutes are developed even in specimens of this age. I have
no hesitation therefore in expressing my belief that this singularly
complete dermal armour will be found to be characteristic of all the
species of the genera _Caiman_ and _Jacare_. On the other hand, I
have examined _Alligator Mississipiensis_, _Crocodilus vulgaris_, _C.
biporcatus_, _C. Americanus_, _C. rhombifer_, and _C. bombifrons_,
_Mecistops cataphractus_, and _Gavialis Gangeticus_, of various ages and
sizes, without having been able to discover a trace of ventral scutes.
This is the more remarkable, as the well-marked ventral and dorsal
shields of many of the ancient _Teleosauria_ would lead one to expect
a corresponding exoskeleton (if anywhere) in their nearest allies, the
modern _Gavialidæ_. However, _Goniopholis_, with its strong armour, is
more like an ordinary Crocodile; and I have recently discovered that a
true Crocodile in some respects curiously similar to _C. bombifrons_
(_C. Hastingsiæ_) was covered with scutes exceedingly like those of the
modern _Caiman_ and _Jacare_.
In minute structure the bony scutes of _Jacare_ closely resemble those
of such a fish as a Sturgeon: a middle layer, containing so many canals
as to appear almost cancellated in longitudinal or transverse section,
is covered externally by a thin, and internally by a thick, layer
composed of bony lamellæ, nearly parallel to the plane of the scute.
Round the canals of the middle layer, the bony lamellæ are disposed
concentrically, to a greater or less extent. The lacunæ are of very
various shapes; and there are perhaps as many short as elongated forms.
The canals of the middle layer communicate by large branches with the
inner, by smaller and fewer branches with the outer surface of the
scute.
In the young _Jacare_ mentioned above, I found the dermis to be
distinguishable into two layers. The more superficial of these is thin,
made up of irregular or formless connective tissue, and contains many
ramified pigment-masses. Its smooth outer surface underlies the rete
mucosum. Internally, it passes into the second or deep layer, which
consists of successive layers of distinctly fibrous connective tissue,
disposed in definite parallel bundles, and having a very regular
arrangement. Throughout a space corresponding with the area of each
scale, in fact, the bundles of each layer cross those of the succeeding
layer at right angles; and the successive tiers of bundles are tied
together by short cords disposed perpendicularly to the planes of the
tiers. A corresponding arrangement of the bundles of connective tissue
has long been known to obtain in the dermis of Fishes and _Batrachia_.
At each end of this small "mat" of connective tissue, the bundles, if
I may so say, fray out; and at the anterior end, the layers, loosened
in texture, bend upwards, spreading out at the same time to become
continuous with the fibres of the "mat" in front. In consequence of
the matting under the quadrate surface of each scale, the dermis has a
peculiar facetted aspect, quite apart from any osseous deposit. Where
bony scutes are formed, they appear as very thin perforated plates in
the most superficial portion of the deep layer of the dermis; so that
there is a single thin layer of dense connective tissue above them,
while below them are all the rest of the denser and deeper lamellæ of
the dermis. Through the apertures in this primitive osseous plate (the
rudiment of the middle layer of the future scute), bundles of connective
tissue extend, connecting the deep with the superjacent lamellæ.
If a thin section is made and decalcified with weak acid under the
microscope, the calcareous matter, as it is dissolved away, leaves an
obscurely fibrous matrix of a different aspect from the surrounding
connective tissue, and the endoplasts, or nuclei, of this matrix are
seen each to have occupied the centre of a lacuna.
Again, the rudimentary scute lies in the dermis as in a sort of pocket,
the superficial and deep walls of which separate from it with great
ease; and in good thin sections made through the dermis and scute, there
seems to be no direct connexion between the substance of the scute above
and below, and the connective tissue with which it is in contact. Nor
could I satisfy myself that the margins of the scute were continuous
with the surrounding bundles of connective tissue. However, the specimen
had been a very long time in spirit; and I am unwilling to lay too much
stress upon these observations, which tend to negative the supposition
that the scute proceeds from the direct calcification of the connective
tissue of the dermis.
On the other hand, I must remark that horizontal sections of the scutes
have presented oblique parallel fissures, sometimes crossing one
another, which might readily be supposed to correspond with the lines of
separation of ossified bundles of connective tissue.
* * * * *
NOTE.--During a recent visit to Paris, my friend Mr. Busk was kind
enough to examine the specimens of recent _Crocodilia_ in the Museum
of the Jardin des Plantes, with reference to certain points to which
I requested his attention. Mr. Busk informs me that there is no doubt
about the transverse direction of the premaxillo-maxillary suture in
_Crocodilus rhombifer_; and his statements lead me to entertain no
question that _C. bombifrons_ is a synonym of _C. palustris_.
In the typical specimens of _C. marginatus_ and _C. suchus_ of Geoffroy
St.-Hilaire, the premaxillo-maxillary suture extends back to the level
of the seventh tooth.
Mr. Busk has furthermore pointed out to me the existence of another
American species of Crocodile--_C. Morelettii_, which has been described
by M. Auguste Duméril in his "Description des Reptiles nouveaux ou
imparfaitement connus," &c., 'Archives du Muséum,' t. vi. 1852.
This species inhabits lake Flores, in Yucatan; and it is said by M.
Duméril to approach _C. Americanus_, from which it differs in the
proportions of the skull and in the characters of the dermal armour.
June 21st, 1859.
* * * * *
On the Habits of the "Aye-Aye" (_Cheiromys madagascariensis_, L.,
Cuv.). By the Hon. H. SANDWITH, M.D., C.B., Colonial Secretary of the
Mauritius. Communicated by Prof. OWEN, F.R.S., V.P.L.S.
[Read April 7th, 1859.]
"Mauritius, Jan. 27, 1859.
"MY DEAR MR. OWEN,--After very great difficulty and much delay, I have
at length obtained a fine healthy male adult _Aye-Aye_; and he is now
enjoying himself in a large cage which I have had constructed for him.
He is a most interesting little animal; and from close observation I
have learnt his habits very correctly. On receiving him from Madagascar,
I was told that he ate bananas; so of course I fed him on them, but
tried him with other fruit. I found he liked dates,--which was a grand
discovery, supposing he be sent alive to England. Still I thought that
those strong rodent teeth, as large as those of a young Beaver, must
have been intended for some other purpose than that of trying to eat
his way out of a cage--the only use he seemed to make of them, besides
masticating soft fruits. Moreover, he had other peculiarities,--_e.g._,
singularly large, naked ears directed forward, as if for offensive
rather than defensive purposes; then, again, the second finger of
the hands is unlike anything but a monster supernumerary member, it
being slender and long, half the thickness of the other fingers, and
resembling a piece of bent wire. Excepting the head and this finger, he
closely resembles a Lemur.
Now as he attacked, every night, the woodwork of his cage, which I was
gradually lining with tin, I bethought myself of tying some sticks over
the woodwork, so that he might gnaw these instead. I had previously
put in some large branches for him to climb upon; but the others were
straight sticks to cover over the woodwork of his cage, which _alone_ he
attacked. It so happened that the thick sticks I now put into his cage
were bored in all directions by a large and destructive grub called here
the _Moutouk_. Just at sunset the Aye-Aye crept from under his blanket,
yawned, stretched, and betook himself to his tree, where his movements
are lively and graceful, though by no means so quick as those of a
squirrel. Presently he came to one of the worm-eaten branches, which he
began to examine most attentively; and bending forward his ears, and
applying his nose close to the bark, he rapidly tapped the surface with
the curious second digit, as a woodpecker taps a tree, though with much
less noise, from time to time inserting the end of the slender finger
into the worm-holes, as a surgeon would a probe. At length he came to
a part of the branch which evidently gave out an interesting sound,
for he began to tear it with his strong teeth. He rapidly stripped off
the bark, cut into the wood, and exposed the nest of a grub, which he
daintily picked out of its bed with the slender tapping finger, and
conveyed the luscious morsel to his mouth.
I watched these proceedings with intense interest, and was much struck
with the marvellous adaptation of the creature to its habits, shown by
his acute hearing, which enables him aptly to distinguish the different
tones emitted from the wood by his gentle tapping; his evidently acute
sense of smell, aiding him in his search; his secure footsteps on the
slender branches, to which he firmly clung by his quadrumanous members;
his strong rodent teeth, enabling him to tear through the wood; and
lastly by the curious slender finger, unlike that of any other animal,
and which he used alternately as a pleximeter, a probe, and a scoop.
But I was yet to learn another peculiarity. I gave him water to drink
in a saucer, on which he stretched out a hand, dipped a finger into it,
and drew it obliquely through his open mouth; and this he repeated so
rapidly, that the water seemed to flow into his mouth. After a while he
lapped like a cat; but his first mode of drinking appeared to me to be
his way of reaching water in the deep clefts of trees.
I am told that the _Aye-Aye_ is an object of veneration at Madagascar,
and that if any native touches one, he is sure to die within the year;
hence the difficulty of obtaining a specimen. I overcame this scruple by
a reward of £10.
I quite despair of obtaining the bones of the _Dinornis_ or _Dodo_,
though I have made every effort. I shall always be proud to be of
service.
Believe me, yours very faithfully,