THE GEOGRAPHICAL DISTRIBUTION OF EARTHWORMS
The facts referred to and considered in the last chapter lead to
further observations upon the geographical distribution of this group
of animals and suggest problems for solution.
It is not the place here to give a general sketch of the division of
Biology termed Zoogeography; but a few general conclusions must be
laid before the reader in order to render what follows intelligible.
It is universally agreed that the range in space (and in time also)
of a given species of animal (or plant) is as much a part of its
scientific definition as are its anatomical characters. A description
for instance of _Acanthodrilus ungulatus_ is incomplete without a
reference to the fact that it occurs in, and is confined to, the
island of New Caledonia.
Each continent or island or part of a continent and part of an
island has its own peculiar inhabitants as well as some others
which range beyond its confines. Thus as we have seen the genus
_Hyperiodrilus_ is confined to the tropical West of Africa while the
genus _Dichogaster_ also found in that region is also met with in
other parts of Africa as well as in certain parts of America and of
the East. In this way the entire globe may be mapped out into regions
characterised by their inhabitants and these regions may also be
further subdivided. The commonly accepted regions were originally
devised by Mr Sclater and are known as the Palaearctic, Nearctic,
Neotropic, Ethiopian, Oriental (Mr Sclater's name was 'Indian'),
and Australian. These regions were originally formed to convey the
facts relative to the distribution of Passerine birds only; but
it is generally held that they apply also to the distribution of
vertebrates generally. The science of zoogeography does not however
end with the display of maps conveying graphically the mere facts of
distribution of this group and that. Its business is also to enquire
into the causes of the affinities between the faunas of different
regions or the varying degree of remoteness which those faunas may
show. On the one hand the varying powers of dispersal and the means
of extending their range possessed by different animals have to be
considered, and on the other hand geological changes in the relative
position of land masses have to be taken into account.
The specific identity between the earthworms of Great Britain and
the adjacent part of the continent of Europe would be very difficult
to understand were we only acquainted with the fact that salt water
is fatal to these animals. But we also know from geology that it
was only at a very recent date that England was cut off from union
with the continent. Thus an identity of fauna was to be expected.
On the other hand we are confronted with a very great difference
between the earthworms of eastern tropical Africa and of the adjacent
island of Madagascar. In the latter we have as a prevalent form the
genus _Kynotus_; in the former continent many Geoscolecidae but no
_Kynotus_. It is believed that the separation of Madagascar from
the mainland was at an earlier date than that of Great Britain from
Europe. We must however be cautious before slipping into what might
seem a case of arguing in a circle. It will however probably not be
disputed that Madagascar was severed earlier than England.
We will now attempt to map out the world into a series of regions
characterised by their earthworm inhabitants and see how far these
regions agree with those rendered necessary by the distribution of
some other animals.
We can to begin with accept the Palaearctic region. The region
however will be a little different from that usually accepted. For
we must probably exclude Japan, whose earthworm fauna contains the
characteristically Eastern genus _Pheretima_. Otherwise we have a
region characterised by the family Lumbricidae, which is really
limited to it, and by just a few traces of other genera such as
_Hormogaster_ among the Geoscolecidae and _Sparganophilus_ which
however is possibly an accidental immigrant. This region is certainly
quite clear. Now according to some persons such as Prof. Heilprin the
northern part of America should be joined with Europe and Asia to
form an Holarctic region; while by most authors, the separate name of
Nearctic is given to the north of the New World. With regard to the
terrestrial Oligochaeta it appears to me that this part of the world
is possibly to be excluded altogether as possessing no indigenous
worms.
In considering the distribution of the Mammalia Sir Ray Lankester
excluded New Zealand from his view as never having possessed any
indigenous mammalian fauna, and termed this part of the world
Atheriogaea. In the same way it is possible that the northern part
of the United States and Canada, whose earthworm fauna consists of
species of Lumbricidae identical with those of Europe, may possibly
be also a region to be excluded in the present survey and spoken of
as 'Ascolecogaea.' In the southern part of the United States we shall
find genera which will be considered presently. On the other hand it
is equally conceivable that this part of the world lost its earthworm
fauna through excessive glaciation in the ice age, the forms having
been driven south and are now only gradually making their way
northwards again. In this case the modern earthworm population which
appears to be absent from large tracts of Canada will be simply due
to involuntary migration. These two views must be left for further
development.
In any case the southern parts of the United States seem to
be separable as a distinct region from South America and to
be characterised by the sub-family Diplocardiinae, the genus
_Diplocardia_ extending as far northwards as the state of Illinois.
The distinctness of such a region however from Central America and
the West Indies is marred by the abundance of _Ocnerodrilus_ of
which Dr Eisen has described so many forms. On the other hand the
West Indies are closely allied in their earthworm fauna to tropical
South America, sharing with that region several forms of Geoscolecids
belonging in both cases invariably to the sub-family Geoscolecinae.
The bulk of the latter are undoubtedly tropical South American in
range and there is no doubt whatever about the distinctness of
this part of the world as a separate region. There is moreover a
further puzzle which confronts us who are trying to delimit an
American region or regions. In North America are species of the
genus _Argilophilus_ which is referred by Michaelsen to the genus
_Plutellus_ which comes from the East and at least one species of
_Megascolides_, also an Eastern genus.
There is at present no doubt to be thrown upon the indigeneity
of _Plutellus_. The species according to Dr Eisen show every sign
of being genuine inhabitants of California and like certain New
Zealand species such as the _Tokea esculenta_ of Benham (referred by
Michaelsen to the genus _Megascolides_) were eaten by the natives. If
these genera were forms restricted to North America, that is not only
with reference to the rest of America but to the world generally,
there would be as I think no doubt about the practicability of
making a Nearctic region. As it is, it seems to me to suit the
facts of distribution better to regard the whole of the land under
consideration as forming one great Neogaean region with three
sub-regions, the North American, Central American and West Indian,
and tropical South American. This region however will not as I take
it include the southernmost extremity of South America. Here in
Patagonia and in neighbouring islands we have a different earthworm
fauna. It is in fact characterised by the sub-family Acanthodrilinae
of which it is true some members of the genus _Notiodrilus_ extend
further north. I shall however defer this part of the subject until
the more easy delimitations of regions are disposed of.
Tropical Africa is evidently to be included in a third region
which will be defined by the Eudrilidae, Microchaetinae among the
Geoscolecidae, and by the great prevalence of _Dichogaster_, a genus
whose occurrence in other parts of the tropics is perhaps not yet
explained satisfactorily. Also we may record as characteristic of
this Ethiopian region a few peculiar genera such as _Nannodrilus_ and
_Gordiodrilus_. _Alma_ being a partly aquatic genus is perhaps less
distinctive and as a matter of fact it strays into the Palaearctic
region, being found in the lower waters of the Nile. It will be
observed that with this exception the limits of the Ethiopian region
according to earthworms agrees with that delimitation afforded by a
consideration of other groups since it stops short at the Sahara,
leaving northern Africa to be referred to the Palaearctic region.
At the same time we have an analogy with South America as concerns
the southern extremity of the African continent; here we meet with
_Notiodrilus_ and allied Acanthodrilinae just as in Patagonia and--as
also in that quarter of the world--these forms just stray into the
Ethiopian region above--specimens of _Notiodrilus_ being met with
in Madagascar as well as in tropical Africa. This bit of Africa as
it appears to me must also be cut off from the Ethiopian region and
included in an Antarctic region. Madagascar offers a further problem.
Are we to include this in Ethiopia or speak of a Malagasy region?
Apart from a few forms which are at least possibly to be looked upon
as accidental immigrants, such as members of the genera _Pheretima_
and _Gordiodrilus_, the fauna of Madagascar consists mainly of
many species of _Kynotus_. This genus, a member of the sub-family
Microchaetinae, of the family Geoscolecidae, affines Madagascar to
Ethiopia and leads me to place both in the same region though we may
doubtless speak of a Malagasy sub-region.
We have now to consider the eastern region of the world comprising
the two regions known generally to zoogeographers as the Oriental
and Australian. Taking a large view of the range of sub-families
and genera, and endeavouring to make the great regions of the globe
more or less equal, it seems difficult to divide further a region
which shall include all of this vast territory, and which may
therefore be termed Indo-Australian. For we find as characteristic
of the entire stretch of country the great majority of the genera
of the huge family Megascolecidae. Indeed the largest sub-family of
this family, _i.e._ the Megascolecinae, is, save for the mysterious
occurrence of the genera _Plutellus_ and _Megascolides_ in America,
absolutely limited to this area. Another sub-family, that of the
Octochaetinae, is limited to it. So far as concerns the others of
the sub-families of Megascolecidae it is only the Trigastrinae
which occur here (the genus _Eudichogaster_ and a few possibly
introduced species of _Dichogaster_) and a scattered species or two
of _Notiodrilus_ of the sub-family Acanthodrilinae. Again there are a
few and probably introduced species of the sub-family Ocnerodrilinae.
More important still this region has confined to itself the family
Moniligastridae; for a species described some years ago by myself
from the Bahamas is doubtless an introduced form. We have a complete
absence of indigenous Lumbricidae and Geoscolecidae excepting the
aquatic _Glyphidrilus_ of the sub-family Microchaetinae. It is true
that by taking isolated tracts, even large tracts, of this great
regional expanse a sub-division into well characterised regions can
be apparently recognised. But in taking such a step we shall be
confronted with the curious fact that it is rather neighbouring than
widely remote sub-divisions which present the greater differences.
If we compare for example India and New Zealand we find in common
such striking genera as _Octochaetus_, _Hoplochaetella_ and
_Diporochaeta_; whereas these genera are absent from the intervening
islands of the great Malay archipelago. On the other hand Australia
differs from the comparatively neighbouring islands of Borneo
and others by the absence in those islands of the characteristic
Australian genera such as _Megascolex_, _Notoscolex_, _Plutellus_
etc. which are in their turn found in India. It is facts like these
which render very difficult the apportioning of the tracts of country
forming the eastern hemisphere into separate regions.
There is no doubt that the Malay archipelago and the adjacent coasts
of Asia up to Japan differ from both India and Australia by the
almost entire limitation of the genus _Pheretima_ to them; but we
cannot intercalate a region in the middle of another geographical
area in this fashion!
The limitations of this great Indo-Australian region now demand
consideration. The chief difficulty is offered by the islands of New
Zealand and by some of the smaller islands lying far from but still
in the neighbourhood of New Zealand. Are we to include New Zealand
in this region? There is no doubt that the northern island of New
Zealand is much nearer to Australia in its earthworm fauna than
is the southern island. There are, it is true, a number of genera
peculiar to New Zealand, which are _Rhododrilus_, _Leptodrilus_,
_Maoridrilus_, _Neodrilus_, _Plagiochaeta_, _Pereiodrilus_,
_Dinodrilus_, _Dinodriloides_, but these do not represent the whole
of any family or even sub-family and they have all of them near
relations in other parts of the region as has been pointed out--even
to the peninsula of India itself. Again New Zealand contains members
of the genus _Notiodrilus_, that characteristic Antarctic form. In
fact New Zealand would appear to be a transitional zone between an
Indo-Australian and an Antarctic region.
The last region into which the world can be divided according to its
fauna of earthworms is an Antarctic. I am of distinct opinion that
this region is quite necessary in spite of the views of some others.
Although the genus _Notiodrilus_ certainly, and _Microscolex_
possibly, extend into the tropical regions of America, Africa, and
Australia, these species are but few, and the bulk of the species
and of the allied genus _Chilota_ are restricted to the antarctic
quarter of the globe; they also extend all over it, that is to say
in the southernmost parts of South America, in the Cape region of
Africa, in Kerguelen and the Crozet Islands, and in New Zealand, as
well as in the Auckland Islands and other neighbouring islands. It is
true that I have excluded New Zealand from this region on the grounds
that it forms a debateable ground between it and the Indo-Australian.
But apart from this part of the world the rest of the territories
mentioned should be combined to form the antarctic region.
Having therefore arrived at a mapping out of the world into regions
in accord with its earthworm fauna, it is desirable to ascertain
what light the facts throw upon the geological and evolutionary
questions with which the study of zoogeography deals. The existence
of an antarctic region binding together such distant points as South
Georgia, the Cape of Good Hope and Kerguelen Island, seems to argue
strongly for the former extensions northwards of the antarctic
continent so far north as to embrace these several regions of that
hemisphere. In view of the facts relating to the danger of sea water
to earthworms, to their lack of facilities for migration, other than
unassisted locomotion, points which have been dealt with earlier, it
is difficult to explain their range in the antarctic hemisphere on
other grounds. The very fact that the actual earthworm fauna of New
Zealand has led us on the whole to assign it to the Indo-Australian
regions shows the inherent uselessness of the current view of
zoogeography. For were we to leave the matter here the relationship
of New Zealand to the regions of the world which lie to the south of
it would not be apparent. However, here as in so many cases there is
an antagonism between cut and dried systems and the indications of
evolution.
This assumed existence of a former antarctic continent which
connected Southern Africa and Southern America as well as various
islands has perhaps a further justification in the distribution of
the Geoscolecidae. This family is divisible into two well-marked
sub-families of which one as has already been mentioned is limited
to South America and another practically to Africa (the exceptions
being species of the largely aquatic _Glyphidrilus_), while a third
sub-family the Criodrilinae is more widely distributed--again in
accordance, one may perhaps assume, with its largely aquatic mode of
life. It is also conceivable that the genus _Dichogaster_ is another
example pointing the same way. The arguments for regarding this genus
as an indigene of the East are not strong. But there is on the
other hand no doubt that the Indian _Eudichogaster_ is very closely
allied to it. But it is by no means excluded from this argument to
suppose that these Trigastrinae owe their likeness to convergence.
At any rate there are examples of equally marked convergence which
seem to be as nearly proved as can be in another though allied
group. The New Zealand _Neodrilus_ is to all intents and purposes a
_Maoridrilus_ in which one of the two pairs of spermiducal glands
and spermathecae has disappeared. It retains the characteristic
alternation in the position of the nephridia of _Maoridrilus_, and
other structural similarities unite the two genera. In the same way
species of _Microscolex_ seem as easily derivable from _Notiodrilus_.
_Microscolex_ and _Neodrilus_ are so near that had we no such hint of
their origin it would be reasonable to place them in the same genus.
They at least show a marked convergence.
It will be noticed therefore that the facts of their distribution
agree, as it would appear, with the structure of the terrestrial
Oligochaeta. The primitive characters of the genus _Notiodrilus_ are
to be seen in the double spermaries and glands appended to the duct,
and the corresponding spermatheca, in the absence, or very slight
development, of the papillae, so frequent in more specialised genera
such as _Pheretima_, and in the general simplicity of many organs of
the body which are more complicated elsewhere. As one would expect
with an archaic form this genus is widely ranging, being found in all
the principal land masses of the globe except in the Euro-Asiatic
continent.
Furthermore geographical facts would at least be not contradictory to
the view that this genus, and therefore the terrestrial Oligochaeta
generally, originated in the Antarctic hemisphere and that in pushing
northwards it has given off various descendants which survive in the
various regions of the world. Basing our views of the possibilities
of range among earthworms on the actual facts already dealt with, it
would seem that the peopling of America from Africa or of Africa from
America, if it has occurred, has not taken place through Europe and
the north generally. For otherwise we should expect traces of the
passage. It is true that we actually have _Hormogaster_ as a possible
sign that the Geoscolecidae have passed this way. But that is an
isolated case and may be referred to the extension northwards of this
particular genus rather than as an indication of a whole migration
through those territories. Another conclusion which a collocation of
the various facts brought together in this book appears to lead to is
that the group of the terrestrial Oligochaeta is relatively speaking
a modern one.
Convinced as we must be of the fact that range is only possible by
unaided locomotion through continuous land areas, the fact that but
few gaps occur in the range of a particular sub-family or lesser
group seems to indicate that no great time has elapsed since the
specialisation of these different forms. The dependence of earthworms
upon vegetable mould also points in the same direction and furnishes
an argument for the belief that these animals only greatly increased
on the advent of abundant dicotyledonous plants, and perhaps indeed
were actually contemporaneous with them.
LIST OF LITERATURE REFERRING TO EARTHWORMS
In the list given below I am only able to mention a few of the larger
works relating to this group. To give anything like a complete list
would demand many pages of titles. From the works selected the reader
can, if it be desired, find his way to the remaining literature of
the group.
A. GENERAL WORKS
Vejdovsky. System und Morphologie der Oligochaeten. Prag, 1884.
Beddard. A Monograph of the Oligochaeta. Oxford, 1895.
Michaelsen. Oligochaeten in 'Das Thierreich.' Berlin, 1900.
Michaelsen. Die Geographische Verbreitung der Oligochaeten, 1903.
Vaillant. Annelès in Suites à Buffon. Paris, 1886.
B. EARTHWORMS OF (1) AUSTRALIA
Fletcher. A series of papers in Journ. Linn. Soc. New South
Wales, 1886-90.
Spencer. A series of papers in Proc. Roy. Soc. Victoria, 1892-5.
Michaelsen. In Die Fauna Südwest-Australiens. Jena, 1907.
(2) NEW ZEALAND AND ANTARCTIC ISLANDS
Benham. Report on Oligochaeta of the Subarctic Islands of New
Zealand. Wellington, N. Z., 1909.
Benham. A series of papers in Quart. Journ. Micr. Sci. 1904,
Proc. Zool. Soc. 1904, 1905 and Trans. N. Z. Inst., 1901-10.
Beddard. In Trans. Roy. Soc. Edinb. 1891 and Proc. Zool. Soc.
1889.
(3) ASIA
Michaelsen. The Oligochaeta of India etc. in Memoirs Indian Mus.,
1909.
(4) EUROPE
Rosa. Revisione dei Lumbricidi. Mem. Acc. Torino, 1893.
(5) AFRICA
Michaelsen. A series of papers in Mitth. Naturhist. Museum.
Hamburg, 1891-1911.
Beddard. Quart. Journ. Micr. Sci., 1890-95.
(6) AMERICA
Eisen. Mem. Calif. Acad., 1894-96.
Cognetti de Martiis. Mem. Acc. Torino, 1905-6.
Rosa. Ibid., 1895.
Beddard. In Hamburg. Magalh. Reise, 1895 and Nachtrag to same by
Michaelsen.
Also numerous other works by the above-named authors and by Perrier,
Horst, Ude, Lankester, Stole, Pierantoni, Friend, Stephenson,
Southern, Goodrich, etc., etc.
INDEX
Aeanthodrilinae, 14, 78, 80, 82, 84, 87, 102
Acanthodrilus, 129
Aeolosoma, 34-36
Aeolosomatidae, 33, 34
African earthworms, 74
Agriodrilus, 31
Allolobophora, 62, 85, 111, 117-119, 128
Alluroides, 40, 41
Alluroididae, 40
Allurus, 45
Alma, 24, 49, 50, 60, 61, 95, 135
Alpine earthworms, 123
Alvania, 75, 115
American earthworms, 71
Amphichaeta, 37
Anachaeta, 42
Anatomy of earthworms, 1
Andiodrilus, 72, 74
Andiorrhinus, 72
Anteoides, 72
Anteus, 72
Antarctic earthworms, 86, 138
Aptodrilus, 72
Aquatic earthworms, 44
Aquatic families of worms, 30
Arctic earthworms, 88
Argilophilus, 93, 133
Asiatic earthworms, 80
Astacopsidrilus, 37, 38
Athecospermia, 39
Aulophorus, 36
Aurantina, 39
Australian earthworms, 83
Barriers to migration, 124
Beddardiella, 76, 95, 115
Benhamia, 72, 92
Bettonia, 76, 115
Bimastos, 117
Bogertia, 75, 114
Books and Memoirs upon earthworms, 144
Bothrioneuron, 38, 39
Branchiura, 38, 39, 70
Branchiodrilus, 36
Buttneriodrilus, 75, 115
Callidrilus, 48, 77
Cape of Good Hope, worms of, 76
Chaetogaster, 37
Chilota, 14, 72, 76, 77, 93, 126, 139
Claparedilla, 39
Climate and distribution, 120
Clitellio, 38, 39, 53
Cocoons of worms, 62, 127
Criodrilinae, 24, 62, 85, 140
Criodrilus, 24, 48, 49, 62, 72, 85, 92, 98
Dendrobaena, 85
Dero, 36, 37
Desmogaster, 81, 94
_Diachaeta_, 73
Diaphorodrilus, 76
Dichogaster, 15, 22, 28, 56, 72, 74, 76, 80, 82, 83, 84, 92, 99,
104, 116-120, 129, 134, 140
Didymogaster, 84
Digaster, 84
Dinodriloides, 87, 138
Dinodrilus, 16, 55, 87, 138
Diplocardia, 85, 133
Diplotrema, 83
Diporochaeta, 19, 80, 84, 87, 94, 111, 137
Dispersal of earthworms, 113
Drawida, 57, 81
Eclipidrilus, 39
Eisenia, 85, 108
Eiseniella, 41, 45, 46, 49, 66, 85
Eminoscolex, 75, 115
Enantiodrilus, 72
Enchytraeidae, 31, 41
Environment, 59
Eudichogaster, 80, 136, 141
Eudrilidae, 25, 26, 28, 29, 61, 66, 75, 78, 86, 116, 134
Eudrilus, 66, 75, 78, 79, 82, 83, 86, 97, 98, 101, 104, 105
Eudriloides, 27, 75, 114
Eupolygaster, 57, 81, 94
Eupolytoreutus, 76
Euscolex, 76, 95, 115
Eutyphoeus, 16, 17, 80
Families of worms, 14
Fimoscolex, 72
Fletcherodrilus, 26, 84
Fresh-water worms, 30, 44
Gardullaria, 76, 115
Genera, range of, 90
Geographical distribution, 129
Geoscolecidae, 20, 22, 23, 46, 59, 61, 71, 76, 79, 86, 104, 132,
134, 136, 137
Geoscolecinae, 22, 23, 71
Geoscolex (= Glossoscolex)
Glossoscolex, 23, 72-74
Glyphidrilus, 48, 49, 77, 79, 83, 98, 137, 140
Gordiodrilus, 76, 78, 81, 92, 99, 106, 135
Haplodrilus, 73
Haplotaxidae, 42
Haplotaxis, 31, 42
Heliodrilus, 75, 115
Helodrilus, 79, 85, 90, 91, 103, 108, 112, 117
Henlea, 41
Hesperodrilus, 38
Hesperoscolex, 23, 58, 72, 73
Holoscolex, 72, 76
Hoplochaetella, 80, 87, 93, 137
Hormogaster, 24, 85, 131, 142
Hormogastrinae, 24, 85
Howascolex, 78
Hyperiodrilus, 30, 75, 115, 117, 129
Hypogaeon, 111
Ilyodrilus, 38
Ilyogenia, 22, 73
Iridodrilus, 76, 115
India, earthworms of, 79
Japan, earthworms of, 131
Kerguelen, earthworms of, 139
Kaffania, 75, 115
Kerria, 18, 73, 99
Kynotus, 23, 24, 29, 78, 95, 97, 131, 136
Lampito, 78, 80
Lamprodrilus, 39, 40
Leptodrilus, 86, 111, 112, 138
Libyodrilus, 28, 75, 115
Light, influence of, 67
Limicolae, 30, 47, 58
Limnodriloides, 31, 38
Limnodrilus, 38, 44
Liodrilus, 73
Lophochaeta, 38
Lumbricidae, 38, 57, 61, 62, 83-86, 90, 103, 104, 107
Lumbriculidae, 37, 41, 48
Lumbriculus, 39
Lumbricus, 85, 90, 108, 120, 122
Lycodrilus, 38
Macrochaetina, 37
Madagascar, earthworms of, 77
Maheina, 14, 78
Malay region, earthworms of, 82, 137
Malodrilus, 76, 115
Man, his influence in distribution, 106, 123
Maoridrilus, 11, 14, 87, 95, 138, 141
Marine worms, 50
Megachaetina, 75, 114
Megadrili, 44, 50
Megascolecidae, 14, 22, 29, 61, 75, 76, 79, 82, 87, 92, 99, 103, 136
Megascolecinae, 19, 22, 80, 82, 84, 87, 136
Megascolex, 19, 55, 62, 64, 80, 84, 93, 99, 137
Megascolides, 80, 84, 87, 93, 133, 134, 136
Mesoporodrilus, 39
Metadrilus, 75, 114
Metascolex, 76, 115
Metschaina, 75, 114
Microchaetinae, 24, 48, 76, 134, 136, 137
Microchaetus, 23, 77, 95
Microdrili, 31
Microdrilus, 92
Microscolex, 14, 72, 74, 83, 84, 94, 99, 102, 103, 106, 107, 139, 141
Migration of earthworms, 113
Millsonia, 92
Moniligaster, 57, 81, 99
Moniligastridae, 29, 41, 57, 61, 81, 83, 86, 94, 98, 137
Naididae, 33-35
Naidium, 37
Nais, 37
Nannodrilus, 18, 76, 135
Nemertodrilus, 75, 115
Nematogenia, 76, 81, 104
Neodrilus, 87, 95, 138, 141
Neumanniella, 76, 115
New Zealand, earthworms of, 86
Nile, worm of, 50
Notiodrilus, 14-16, 20, 22, 37, 47, 52, 72, 74, 76, 77, 83, 84,
86, 91-94, 111, 122, 126, 134-139, 141
Notoscolex, 80, 84, 93, 137
Notykus, 75, 114
Ocnerodrilinae, 16, 32, 73, 76, 81, 136
Ocnerodrilus, 18, 22, 73, 76, 78, 81, 84, 92, 99, 133
Octochaetinae, 16, 80, 84
Octochaetus, 16, 62, 80, 87, 93, 94, 137
Octolasium, 85, 117
Oceanic islands, earthworms of, 109
Onychochaeta, 23, 72, 73
Opisthodrilus, 72
Papillae, 64
Paranais, 36, 125
Parascolex, 75, 115
Pareudrilus, 75, 115
Patagonia, worms of, 139
Pelodrilus, 42, 111, 112
Peloryctes, 39
Peregrine species, 96
Pereiodrilus, 87, 138
Perichaetidae, 104
Perionyx, 19, 22, 82, 84, 95, 99
Perionychella, 84
Periscolex, 23, 56, 72, 73
Perissogaster, 84
Pheretima, 19, 23, 55, 60-64, 73, 78, 80, 82, 84, 90, 94, 99, 102,
104, 105, 110, 111, 122-124, 131, 135, 138, 141
Phreatothrix, 39
Phreodrilidae, 37
Phreodrilus, 37, 38, 70, 111
Phreodriloides, 38
Phreoryctes (= Haplotaxis)
Plagiochaeta, 15, 55, 87, 111, 138
Platydrilus, 75, 114
Pleurophleps, 35
Plionogaster, 19, 29, 82
Plutellus, 80, 84, 87, 93, 95, 111, 133, 134, 136, 137
Polytoreutus, 25, 26, 58, 76
Pontodrilus, 50, 51, 125
Pontoscolex, 20, 22, 23, 66, 72-74, 78, 79, 82, 83, 96, 97, 98,
101, 102, 104, 105, 111
Preussiella, 75, 115
Pristina, 37
Psammoryctes, 38
Pygmæodrilus, 76
Reithrodrilus, 75, 114
Rhinodrilus, 72, 73
Rhizodrilus, 39
Rhododrilus, 86, 111, 138
Rhynchelmis, 39
Ripistes, 86
Rosadrilus, 75, 115
Sea-shore, worms of, 50
Sea as a barrier, 124
Schmardaella, 36
Senses of worms, 65
Sparganophilus, 24, 47, 85, 92, 132
Spenceriella, 80, 84, 87
Structure (_see_ Anatomy)
Stuhlmannia, 75, 114, 117
Stylaria, 37
Stylodrilus, 39
Sutroa, 39
Systematic arrangement, 14
Teleudrilus, 76, 115
Teleutoscolex, 39, 40
Teleutoreutus, 76, 115
Telmatodrilus, 38
Temperature and distribution, 120
Thamnodrilus (_see_ Rhinodrilus)
Titanus, 23
Tokea, 87, 134
Trichochaeta, 23, 53
Trichodrilus, 39
Trigaster, 80, 84, 85
Trigastrinae, 15, 72, 80, 82, 84, 136
Tritogenia, 77
Tubifex, 38, 44
Tubificidae, 33, 37, 38, 48
Tykonus, 72
Urobenus, 72
Urochaeta, 20
Vejdovskyella, 37
Vermiculus, 39
Woodwardia, 80, 82, 84, 93
Yagansia, 14, 72, 74, 76, 93
Zapotecia, 85
CAMBRIDGE: PRINTED BY JOHN CLAY, M.A. AT THE UNIVERSITY PRESS
End of Project Gutenberg's Earthworms and their Allies, by Frank E. Beddard