F 
f 
MARSUPIALIA. 
lection of experienced surgeons which have 
been dispersed by some one or other of the 
remedies in ordinary use, local or constitu- 
tional; and how many that have resisted all 
and remained stationary for years, the patient’s 
mind having been tranquillized by the assur- 
ance of their innocency. Doubtless on- the 
other hand a fatal result has sometimes ad- 
ministered a silent but painfully intelligible 
reproof to the over-confidence of the surgeon.” 
(Samuel Solly.) 
MARSUPIALIA, ( Marsupium, a pouch,) 
Eng. Marsupials; Fr. Marsupiaux ; Ger. Beu- 
telthiere. 
Essential external character— Mammalian 
quadrupeds, distinguished by a peculiar pouch 
or duplicature of the abdominal integument, 
which, in the males, is everted and contains the 
_ testes; in the females is inverted, covering the 
_ mamme, and generally sheltering the young for 
_ a certain period after their birth. 
 centa. 
BO 
Essential internal character —In both sexes 
two supplementary trochlear bones are articu- 
lated to the anterior part of the brim of the 
steed around which play the muscles em- 
racing and supporting the testes in the male, 
and the mammary glands in the female; these 
bones, from their connexion with the pouch, 
are called “ marsupial.” 
The quadrupeds associated together by the 
common external and osteological characters 
above defined, are ovo-viviparous or impla- 
cental,* the vascular layer of the allantois not 
_ being developed, so as to organize the villi of 
_the chorion, or to form cotyledons or a pla- 
The marsupial also differ from the 
placental Mammalia in other important parts 
of internal organization, as in the structure of 
the brain and of the heart, and in the con- 
dition of the sanguiferous and absorbent sys- 
tems; and they present remarkable modifica- 
tions of the genital apparatus in both sexes. 
Classification —The Marsupial animals are 
generally of small size; some, as the Pigmy 
m (Petaurus pygmaeus), and Dwarf 
_ Phalanger ( Phalangista nana), are less than 
_ the common mouse : the largest known existing 
“species is the common or Great Kangaroo 
Peleropus major). With the exception of 
‘the Virginian Opossum, all the Marsupialia 
are confined to the southern hemisphere of the 
globe, and they are pe y natives of Aus- 
tralasia, to which part of the world several 
remarkable genera are peculiar, and where, with 
a few exceptions, as certain Cheiroptera and a 
few Rodent genera, as Hydromys, Hapalotis, 
and Pseudomys, all the known aboriginal 
mammals are Marsupial or Monotrematous.+ 
It is in the Australian continent that we per- 
ceive the Marsupial quadrupeds typifying, so 
to say, or playing corresponding parts with 
those allotted to the placental Mammalia ina 
larger theatre of the habitable surface of the 
* On the Generation of the Marsupialia, Philos. 
Trans. 1834, p. 333. 
+ The Dingo or Wild Dog is without doubt a 
comparatively recent and accidental introduction. 
VOL. III. 
257 
earth. The carnivorous Thylacines*_and Da- 
syures,+ for example, are the pigiffy destruc- 
tives of the country, committing occasional 
ravages among the sheep and poultry, but not 
disdaining dead animal matter or garbage. 
The species of Phascogale, Myrmecobius, 
and Perameles represent the placental Insec- 
tivora. Many Murstiiols which live in trees 
have an omnivorous or vegetable diet ; these in 
their prehensile tail and hinder thumb typify 
the Quadrumana ; and one species, the tailless 
Koala, seems to represent the American sloths 
or the arboreal sun-bears of the Indian Archi- 
pelago. 
Another species of Marsupial, the Wom- 
bat, presents the dentition which characterizes 
the placental Rodentia; and the Petaurists, 
like the flying squirrels, have a parachute 
formed by broad duplications of the skin ex- 
tending laterally between the fore and hind legs. 
The Kangaroos are the true herbivorous 
Marsupialia, and many interesting physiolo- 
gical conditions present themselves to the mind 
in contemplating the singular construction and 
proportions of these animals. It would ap- 
pear that the peculiarities of their gestation 
rendered indispensably necessary the posses- 
sion of a certain prehensile faculty of the 
anterior extremities, with a free movement of 
the digits and a rotatory power of the fore-arm, 
in relation to the manipulations of the pouch 
and of the embryo therein protected and ma- 
tured. At the same time an herbivorous quad- 
ruped must possess great powers of locomo- 
tion in order to pass from pasture to pasture, 
and to avoid its enemies by flight. These 
owers, as is well known, are secured to the 
erbivorous species of the placental Mammalia 
by an ungulate structure of four pretty equally 
developed members. Such a structure, how- 
ever, would have been incompatible with the 
procreative economy of the Kangaroo. It is, 
therefore, organized for a rapid course by an 
excessive development of the hinder extre- 
mities, and these alone serve the animal in 
flight, which is performed by a succession of 
extensive bounds. The tail, also, is of great 
power and length, and, in the stationary po- 
sition, the body is supported erect on the tripod 
formed by the tail and hind legs, while in easy 
progression the tail serves as a crutch, upon 
which and the fore feet the body is sustained 
while the hind legs are swung forwards. 
‘As the Australian Continent, the great me- 
tropolis of the Marsupial quadrupeds, still 
remains but very partially explored, and as 
new species and even genera of Marsupials 
continue at each expedition to reward the re- 
searches of the scientific traveller; and as, more- 
over, the recovery of two lost but distinct 
genera from the ruins of a former world makes 
it reasouable to suppose that other types of 
Marsupials remain still hidden in the crust of 
the earth, it can hardly be expected that the 
zoologist should be able to arrange in a natural 
series, with easy transitions according to the 
* The Hyzna of the Colonists. 
+ The Devil, Native Cat, &c. of the Colonists. 
Ss 
