The zone of glands at the commencement of the duodenum has been already noticed ; they are present in other Marsupials, even in the most carnivorous species ; but I have not met with a similar structure in the placental Mammalia. The villi of the small intestines in the Kangaroo are of moderate length, com pressed and close-set. Glandulm aggregate are arranged in narrow patches in the ileum. There are seven groups of similar follicles in the CCeCIIM ; and a few long and narrow patches of glands occur in the colon intermingled with numerous glanduhe solitarim; the surface of the rest of the lining membrane of the large intes tine is disposed in a very fine net-work.
Two faint longitudinal bands extend along the first ten inches of the colon and are con tinued two-thirds of the ccecum the sacculi produced by these bands are but very feebly marked. I have not met with any ex ample in the Macropus major of a ccecum, which, either naturally or when inflated and dried, presented the sacculated structure repre sented by Cuvier in fig. 8, pl. xxxix. of the Lecons d'Anat. Compare.
The contents of the ccecum in the great Kan garoo are of a pultaceous consistence, and the mass continues undivided along the first two feet of the colon, gradually becoming less fluid and then beginning' to be separated into cubical faeces about an inch square. The diameter of the large intestine in this species exceeds very little that of the small intestines.
In all the Marsupials two sebaceous follicles open into the termination of the rectum. The anus has its proper sphincter, but is also sur rounded, in common with the genital outlet, by a larger one. When the penis is retracted, the faecal, urinary, and genital canals all ter minate within a common external outlet; so that in the literal sense the Marsupials are mo notrematous.
The following is a table of the length of the intestinal canal, and its parts in a few species of the different families of Marsupialia.
Salivary glands.—These glands in the Car nivorous Dasyures consist of a small parotid and a large submaxillary gland on each side. I searched expressly, but in vain, for the zygo matic gland ; the Dasyures do not agree with the dogs in having these glands. They have no sublingual gland. The submaxillary gland is placed in front of the neck, so that its duct passes on the dermal side of the tendon of the hiventer maxilla', and terminates half an inch from the symphysis menti. There is a thick row of
labial glands along the lower lip. The Opos sums and Bandicoots present a similar salivary system.
In the Phalairgista vulpitia there is a sub lingual gland on each side of a firm texture, about one inch in length and three lines broad ; a roundish submaxillary gland about the size of a hazel-nut; and a broad and flat parotid, larger than in the Entomophagous or Sarco phag,ous Marsupials.
The parotid glands are relatively larger in the Koala, in which the duct takes the usual course over the masseter and enters the mouth opposite the third true molar, counting back wards.
In the Wombat I found the parotid glands very thin, situated upon both the outer and inner side of the broad posterior portion of the lower jaw ; the duct passed directly upwards and outwards to the insertion of the sterno cleido-mastoideus ; here it was buried in the cellular substance anterior to that muscle, then turned over the ramus of the jaw, and, pur suing a somewhat tortuous course over the masseter, entered the mouth just anterior to the edge of the buccinator. The submaxillary glands were each about the size of a walnut ; their ducts terminated as usual on each side of the frxnum In the great Kangaroo the parotid is very large, extending from below the auditory mea tus three or four inches down the neck. In the Ilypsipryninits it reaches as far as the cla vicle. In both cases this gland is separated from the submaxillary gland by the submaxil lary vein.
The tonsils are small in all the Marsupials, but are not represented in the carnivorous spe cies, as in the Placental hers, by simple glan dular pouches at the sides of the faeces; for example, they consist of an oblong glandular body on each side in the Dasyurus macrurus.
The liven—The liver is subdivided into many lobes in all the Marsupial genera. It is relatively largest in the burrowing Wombat and carnivorous Dasyure; relatively smallest in the graminivorous Kangaroo, in which it is situated, as in the placental Ruminants, en tirely to the right of the mesial plane. The small or Spigelian lobe, which fits into the lesser curve of the stomach, is given off from the left lobe of the liver in the Kangaroos, but from the right in most other Marsupials ; the difference just noticed in the Kangaroo depends on the peculiar disposition of its remarkable stomach.