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Spaniards by following them up, first discovered the watering-places. When 1
landed at Chatham Island, I could not imagine what animal travelled so methodi-

* ~

cally along well-chosen tracks. Near the springs it was a curious spectacle to
behold many of these huge creatures, one set eagerly travelling onwards with
outstretched necks, and another set returning after having drunk their till.
When the tortoise arrives at the spring, quite regardless of any spectator, he
buries his head in the water above his eyes, and greedily swallows great mouth-
fuls, at the rate of about ten in a minute. The inhabitants say that each animal
stays three or four clays in the neighbourhood of the water, and then returns to
the lower country; but they differed respecting the frequency of these visits."
After mentioning that some tortoises live on islands where the only water they
obtain is that which falls as rain, and also that the inhabitants of the Galapagos
Islands, when overcome with thirst, are in the habit of killing a tortoise and
drinking the water contained in its interior, the writer proceeds as follows : " The



LAND-TORTOISES. 59

tortoises, when purposely moving towards any point, travel by night and day,
and arrive at their journey's end much sooner than would be expected. The

.inhabitants, from observing marked individuals, consider that they travel a
distance of about eight miles in two or three days. One large tortoise, which I
watched, walked at the rate of sixty yards in ten minutes, that is three hundred
and sixty yards in the hour, or four miles a day, allowing a little time for it to
cat on the road. During the breeding-season, when the male and female are
together, the male utters a hoarse roar or bellowing, which, it is said, can be heard
at a distance of more than a hundred yards. The female never uses her voice, and
the male only at these times ; so that when the people hear this noise, they know
that the two are together. They were at this time (October) laying their eggs.
The female, where the soil is sandy, deposits them together, and covers them up
with sand ; but where the ground is rocky, she drops them indiscriminately in any
hole ; Mr. Bynoe found seven placed in a fissure. The egg is white and spherical ;

,one which I measured was 7f inches in circumference, and therefore larger than a
hen's egg. The young tortoises, as soon as they are hatched, fall a prey in great
numbers to the carrion-feeding buzzard (Polyborus). The old ones seem generally
to die from accidents, as from falling down precipices ; at least, several of the
inhabitants told me that they never found one dead without some evident cause.
The inhabitants believe that these animals are absolutely deaf ; certainly they do
not hear a person walking close behind them. I was always amused when over-
taking one of these great monsters, as it was quietly pacing along, to see how
.suddenly, the instant I passed, it would draw in its head and legs, and uttering a
deep hiss fall to the ground with a heavy sound, as if struck dead. I frequently
got on their backs, and then giving a few raps on the hinder part of their shells,
they would rise and walk away ; but I found it difficult to keep my balance."

Like their Mascarene allies, the Galapagos tortoises are much esteemed as
food ; and in order to see whether they were sufficiently fat to be killed, the
inhabitants were accustomed to make a slit beneath the tail, through which the
interior of the body could be seen. With the usual hardihood of reptiles, the
rejected individuals appear to have recovered completely from this severe
operation. From several of the islands the giant tortoises have already dis-
appeared, and it is much to be feared that they will soon cease to exist throughout
the Galapagos Group. Dr. G. Baur, who visited Albemarle in 1891, reports,

: however, that he made a large collection of these reptiles, one specimen weighing
more than 400 Ibs., and its carapace measuring 4 feet in a straight line.

The familiar Grecian tortoise (T. grceca) brings us to the sixth

Grecian Tortoise. . . /YIJTIT u

main group or the genus, which comprises seven Old World species or

small or medium size, characterised by the carapace being brown or olive, which

' may be either uniform, or spotted with black, or black and yellow ; by the gular

shields on the plastron being distinct; and by the slight prominence and shortness

of the ridge on the palate. The Grecian tortoise belongs to a section of the group

in which the anal or hindennost shields of the plastron meet in the middle line by

j a suture of considerable length ; and it is further characterised by the presence of

\ five claws on the fore-foot. From its nearest allies it may be distinguished by the

! fifth vertebral shield of the carapace being much broader than the third; the



6o



TORTOISES AND TURTLES.



caudal shield being usually double, and there being no large tubercle on the inner
.side of the thigh. The shell of this species is moderately vaulted, and not much
expanded behind, while its margins are not serrated. The nuchal shield is very
long and narrow; in the male the divided caudals are much incurved; and tin-
shields of the back show a strongly-marked concentric striation. In colour, 1 lie
shell is bright yellow, with the shields of the carapace spotted and bordered with
black, and a broad band of black running along each side of the plastron. The
length cf the shell is about 5 inches. Mainly a South European species, the
Grecian tortoise inhabits the Balearic Islands, Corsica, Sardinia, Sicily, Italy,
Dalmatia, the Balkan Peninsula, and the Greek Archipelago, while it also occurs in
Syria. The allied but larger Algerian tortoise (21 ibera), in which the shell attains
a length of about 9 inches, may be distinguished by the fifth vertebral shield being
not broader than the third, by the single caudal shield, and the presence of a large

subconical tubercle on the inner

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surface of the thigh. In colour,
this species differs from the last
in having the plastron more or
less spotted with black, while
in some examples the carapace
is uniformly brown. Its range
includes North-Western Africa,
Syria, Asia Minor, Trans-
caucasia, and Persia. A third
species often represented aim mg
the shiploads of these reptiles
imported into England, is the
margined tortoise (T. man
ginata), which attains a length
of 11 inches, and appears to
be confined to Greece. The
absence of an enlarged tubercle on the thigh serves to distinguish it from the
preceding species ; from which it also differs by the longer and more depressed shell,
in which the hinder margin is much expanded, and more or less serrated. Usually
the carapace of the adult is black with a small yellow or greenish spot on each
shield; while the ground-colour of the plastron is yellowish, each of its shields
being marked by a black patch, which generally takes a triangular form. This
species appears to be confined to Greece ; but in Lower Egypt and Syria is replaced
by the smaller Leith's tortoise (T. leitki), in which the carapace is relatively shorter
and more deeply notched in front, while the form and arrangement of the tubercles
on the fore-limb is different.

All these tortoises appear identical in their habits, frequenting dry and sandy
places, and being extremely fond of sunshine, in which they will bask by the hour
together. In certain parts of Greece and the south of Italy, the Grecian tortoise is
found in great numbers ; and in the markets of Sicily and Italy it is regularly
exposed for sale as an article of food. At the approach of winter it buries itself
deep in the earth, where it remains during the cold months, usually reappearing in




GRECIAN TORTOISE.



LAND- TOR TO1SES. 6 1

April, but in Sicily as early as February. Although its main food consists of
plants and fruits, it will likewise consume such snails, worms, and insects as it
may meet with during its wanderings. In captivity, where they have been known
to live for a great number of years, these tortoises display great partiality for
milky plants, such as lettuce; and they are always fond of a bath. At the
approach of rain they always hide themselves, but in fine weather remain abroad
throughout the day. In excavating a burrow for the winter's sleep, the earth is
dug up by the strong fore-limbs, and thrown out from the hole by the hinder pair.
The pairing-season commences immediately after the awakening from the winter
sleep; and in May or June the female lays from eight to fifteen hard-shelled white
eggs, of about the size of a hazel-nut. These are deposited in a hole in the earth
in some sunny spot, and after being carefully covered up, are left to hatch. By
September the young tortoises are about the size of half a walnut-shell, and
present an exceedingly comic appearance.

There are certain other species belonging to the same group as
Other Species. . . l . to to .

the Grecian tortoise, which demand a brief notice. Among these is

the handsome elongated tortoise (T. elongata), from Bengal, Burma, Cambodia, and
Cochin China, taking its name from the great length of the depressed shell of the
males ; the females being much smaller, with a relatively shorter and wider shell.
These tortoises differ from the European species by the anal shields of the plastron
having a very short line of union in the middle, even if they meet at all. The
ground-colour of the shell is greenish yellow, upon which is an irregular black
patch in each shield, which may occupy nearly the whole area of such shields,
leaving merely a narrow yellow margin, or may be much broken up and indistinct.
.The male attains a length of between 10 and 11 inches. Forsten's tortoise (T.
forstent), from Celebes and Gilolo, may be distinguished by the want of a nuchal
shield in the front of the carapace. Lastly, we have Horsfield's tortoise (T.
liorKfield-i), which, while allied to the European species, differs in having but four
; claws on the fore, as well as on the hind-feet. This tortoise inhabits the deserts,
oases, and even mountains of Central Asia, where it ranges from the Aralo-Caspian
region and the Kirghiz Steppes to Afghanistan. The shell, which is considerably
depressed and not much longer than broad, has a brown or olive ground-colour
above, which may be either uniform or blotched with black ; while beneath, it has
large patches of black, which sometimes almost cover the whole surface.

Writing of the elongated tortoise, Dr. J. Anderson says that it is active in its
habits, and that the male is very confiding, eating readily from the hand, although
the female, when touched, at once withdraws within the shell. Captive specimens
were observed to be very restless at night ; they feed freely on plantains, but a
female on occasion ate some dead prawns and fish, which had been procured to feed
some soft- tortoises. Horsfield's tortoise, although equally fond of immersing its
lower shell in water, is said to be more brisk in hot weather than are the European
species ; it is purely diurnal in its habits, not venturing forth till after sunrise, and
retiring to rest before sunset. Its food in the wild state is stated to be entirely of
a vegetable nature ; snails and worms being never eaten.

Anguiated The angulated tortoise (T. angulata), of South Africa, together

Tortoise. w ith an allied species (T. yniphora) from an island near the Comoros,



62



TORTOISES AND TURTLES.



constitute the last and sevcntli group of the genus, and are distinguished from all
the others by the great prolongation of the anterior extremity of the plastron, which
is covered by a single gular shield only. The former attains a length of about 7.1
inches, and has an elongated and very convex carapace, of which the hinder margin
is at most but slightly serrated. In colour, the shell is yellow above, each shield
being bordered with black, and usually ornamented with a black spot in the
centre ; while the plastron is black in the middle, or has some large black blotch rs.
Areoiated Nearly related to the true tortoises, with which it agrees in the

Tortoise. general structure of its shell, the areolated tortoise (Homopus areo-
latus), of South Africa, together with three other allied species from the same
continent, differs by the absence of the median ridge on the front of the palate
characterising all the former, and is on this account referred to a distinct genus.

If the horny shields be stripped
from the carapace, it will be
found that the underlying neural
bones, instead of being alter-
nately octagonal and quadran-
gular, are irregularly hexagonal,
with the shorter of the two
lateral surfaces placed posteri-
orly ; since, however, the same
feature occurs in some of the
true tortoises, it is not absolutely
characteristic of the genus. The
areolated tortoise is a small
species, with a shell of only 4
inches in length. It is char-
acterised by having only four
claws on the front feet, and l>y
its depressed carapace, which is of equal width throughout, and has even margins.
On the back, the shields are more or less inflated, and separated from one anot
by deep channels ; the centre of each shield having a depressed areola, surround'
by concentric grooves. In colour, the carapace is olive, with a reddish brow
centre to each shield; while the plastron is brown in the middle, and yellow
the edges. A second species (H. femoral is) differs by having the hinder margin
the shell serrated, and a conical tubercle on the hinder surface of the thigh;
while in a third (H. siynatus), there are five toes on each fore-foot. Lastly. //.
nogueyi differs from all the others in its vaulted carapace, which is gibbose behind ;
this species being from Senegal, while the other three are South African. In
general habits it is probable that the members of this genus closely resemble th
true tortoises.

Three remarkable tortoises inhabiting tropical Africa constit

68> a genus distinguished at a glance from the other members of this

section of the family by the circumstance that the hinder portion of the carapace

is articulated to the anterior moiety by a ligamentous hinge, upon which it is

freely movable, so that when the animal is withdrawn the hinder extremity of




AUEOLATED TORTOISE.



HINGED TORTOISES.



11 ic shell can bo completely closed. This hinge runs between the fourth and fifth
costal bones and the seventh and eighth marginals of the shell. The skull agrees
with that of the preceding genus, in the absence of a median ridge on the front of
the palate, while the neural bones of the carapace are hexagonal and short-sided
behind, and the caudal shield is undivided. The costal bones of the carapace
difl'er, however, from those of the tortoises described above, in being of nearly
equal width throughout, instead of alternately narrow at one end and broad at
the other. Of the three species of the genus, the dentated hinged tortoise (Cinixys
t), from Guinea and the Gabun, is characterised by the front and hind margins




DENTATED HINGED TORTOISES (J liat. size).

the carapace being everted and strongly dentated ; by the absence of a nuchal
shield, the projection of the extremity of the plastron in front of the carapace, and
the .sloping contour of the hinder extremity of the latter. The length of the shell
is !) inches; its general colour above being dark brown, with lighter centres to the
shields, and the lower sides of the costal shields yellowish; while on the plastron
the shields have dark brown centres and yellowish margins. In the nearly allied
Home's hinged tortoise (C. homeana), from the same regions, there is a nuchal
shield, the extremity of the plastron does not project in advance of carapace, and
thi- hinder extremity of the latter descends vertically. On the other hand, Bell's
hinged tortoise (('. Lcll/Adta.), which ranges right across tropical Africa, the margins
of the carapace are neither everted nor serrated; a nuchal shield being present on
the front of the carapace. In length the latter does not exceed 7J inches.



6 4



TORTOISES AND TURTLES.



In habits the hinged tortoises show a complete transition from the land
tortoises to the terrapins, and thus fully justifies the conclusion, arrived at from
structural considerations, that both groups should be included in a single family.
According to the observations of Monteiro, it appears that Bell's hinged tortoise is
essentially a land reptile, inhabiting regions formed of gneiss rocks or other dry
localities, where it is active during the hot rainy season, but in the cooler portion
of the year, from May to October, according to native reports, lies deeply buried in
the earth. Both the other species, on the contrary, seem to be mainly aquatic in
their habits; the dentated hinged tortoise, which is fairly common in Guinea, being

stated to spend a large portion
of its time in the water, where
one specimen remained for up-
wards of a month. According
to Falkenstein, it is found in
rivers, even close to the sea,
from whence it emerges to lay
its eggs on their banks. In
spite of its club -like feet, it
dives and swims with facility;
captive examples descending to
the bottom of a deep vessel in
which they were kept. On
land, its motions are, however,
slow and deliberate in the
extreme ; and have been COIR-
BELL'S HINGED TORTOISE. pared to those of the minute-
hand of a clock. Its food is

of a vegetable nature ; one captive specimen displaying great partiality for cherries.
By the inhabitants of Guinea these tortoises are eagerly sought after as food, am 1
are thus difficult to obtain by Europeans.

The last member of this section of the family is the spide
ise> tortoise (Pyxis arachnoides) of Madagascar, which is the sol
representative of a genus characterised by the presence of a transverse hin<
across the front of the plastron, by which means the anterior lobe of the latter cr
be bent upwards so as to close the front of the shell. In having the neural bont
of the carapace alternately octagonal and tetragonal, this species approaches tl
true tortoises nearer than do the hinged tortoises. In length the shell is only jv
over 4 inches ; its coloration is yellow, with radiating black bands from the centi
of the shields of the back.

The whole of the tortoises hitherto described are collective!
Land-Terrapins. chttracterised by the absence of all trace of webbing in the toes, by
the presence of not more than two joints, or phalanges in each toe, by the meta-
carpal bones of the fore-foot being but slightly, if at all, longer than wide, and
also by the majority of the bony neural plates of the carapace being hexagonal.
with their shorter lateral surfaces posteriorly placed, or alternately octagonal and
tetragonal. On the other hand, in the remaining members of the family, the




LAND-TERRAPINS. 65

digits are usually furnished with webs, or at least a rudiment thereof, while the
middle toe of each foot has three joints, and the metacarpal bones are elongated.
\Yr have h'rst to deal with a small group, mainly confined to the Oriental region,
which both in structure and habits tends to connect this section of the family
with the preceding one. These forms, as shown in the right-hand figure of the
illustration on p. 42, agree with the hinged tortoises in that most of the hexa-
gonal neural plates of the carapace have the shorter of the two lateral surfaces
placed posteriorly and the longer anteriorly. Moreover, if the horny shields from
the plastron be removed, it will be found that the entoplastral, or median unpaired
bone of that part of the skeleton, is crossed by the groove marking the boundary
between the humeral and pectoral shields.

spinose Land- The spinose land-terrapin (Geoemyda spinosa) may be taken as

Terrapin. a well-known example of the first genus, characterised by the absence
of a hinge in the plastron, and of a bony temporal arch on the sides of the skull.
The three species of this genus are large-sized tortoises, confined to Burma and
the Malayan region ; the spinose land-terrapin having a shell of 8 inches in length,
while that of the great land-terrapin (Gr. grandis), from Burma and Siam, measures
upwards of 16 inches. In the former of these two species both the front and
hinder margins of the shell are deeply serrated ; whereas in the latter, as well as
in the third representative of the genus, only the hinder border is thus ornamented.
The colour of the carapace in these terrapins is brown or blackish, frequently with
darker markings. Together with the other members of the group, they differ from
the majority of the terrapins in having the head covered with a continuous skin,

istead of with small shields. The small size of the webs of these terrapins

dicates that in habits they are probably in part aquatic and in part terrestrial.
Chaibassa The Chaibassa terrapin (Nicoria tricarinata) figured in the

Terrapin. illustration on p. 66, and taking its name from a district in Bengal,
selected to represent a genus common to the Oriental region in the east, and
Central and South America in the west, distinguished from the preceding by the
presence of a bony temporal arch to the skull. Of the seven species of this genus,

le smallest (here figured) has a shell of only 5 inches in length, but in a larger
it may measure as much as 16 inches. While in the figured Chaibassa terrapin

>th fore and hinder margins of the shell, as shown on the left-hand figure on
p. 42, are entire, in other species either one or both of these may be deeply
serrated. The Chaibassa species, which ranges from Bengal to Assam, has the
carapace dark brown or black in colour, with the three longitudinal ridges from
which it takes its name yellow ; the plastron being uniformly yellow, and the
neck arid limbs blackish. From the larger three-keeled terrapin (N. trijuga),
of India and Burma, this species is further distinguished by its more convex shell,
which descends very abruptly behind, as well as by the rudimentary condition of
the webs between the toes ; on both of which grounds it may be regarded as more
exclusively terrestrial in its habits. A fossil shell of the Chaibassa terrapin,
represented in the right figure on p. 42, has been obtained from the Pliocene
rocks of the Siwalik Hills of Northern India, thus indicating the extreme
antiquity of the species. In some individuals the hinder half of the plastron
is connected with the upper shell merely by ligament.

VOL. V. 5



66 TORTOISES AND TURTLES.

Hinged The third genus of this group (Cyclemys), which is confined to

Terrapins. India, Malay ana, and the south of China, is represented by some
half a dozen species, which, while agreeing with the members of the foregoing
genus in the presence of a bony temporal arch to the skull, differ by having a
well-marked transverse ligamentous hinge across the middle of the plastron,
whereby its hinder lobe is rendered movable, and capable of more or less com-
pletely closing the posterior aperture of the shell. None of the species have a
shell of more than 8 inches in length. The genus may be subdivided into two
groups, each containing three species. In the former, as represented by C. dhor,
of Northern India and the Malayan region, the plastron, which is notched behind,
cannot completely close the shell ; while the hinder margin of the carapace is
serrated. In the second group, on the other hand, of which the Amboyna hinged
terrapin (C. amboinensis) is a familiar example, the plastron is capable of
completely closing the hinder aperture of the shell, while the posterior margin




CHAIBASSA TERRAPIN ( nat. size).

of the carapace is not serrated. These species also have the shell keeled on the
back in the young state. In the Amboyna species, as also in C. flavomarginata,
the hinder end of the plastron is entire, although in a third (C. trifasciata) it
is notched.

Agreeing with the hinged terrapins in the presence of a trans-
Box-Tortoises.

verse ligamentous hinge across the middle of the plastron, by the aid

of which the openings of the shell can be closed, the two North American species
of box-tortoises, together with all the remaining members of the family, differ
from the former in that the hexagonal neural bony plates of the carapace have
the shorter of their two lateral surfaces placed anteriorly, instead of posteriorly,
this arrangement being shown when the shell is stripped. The presence of
the hinge in the plastron serves to distinguish the box-tortoises from all Hie
members of the second group, with the exception of the pond-tortoises, while from



Online LibraryRichard LydekkerThe new natural history (Volume 5) → online text (page 8 of 62)