106 



and the latter giving off the Spigelian lobe. The large gall-bladder 

 was loosely suspended in a deep cleft of the right lobe. The coats 

 of the ductus choledochus are thickened before the termination of the 

 duct, in common with that of the pancreas, in the duodenum. The 

 spleen, as in the Great Kangaroo, is T-shaped. 



The heart showed the usual marsupial structure in the presence of 

 the two distinct superior venae cavse, and the absence of the ' fossa ' 

 and ' annulus ovalis.' Both right and left lungs were cleft at their 

 anterior margin, and a large azygos lobe was developed from the 

 former, and occupied the part of the posterior mediastinum between 

 the pericardium and diaphragm. 



The larynx agreed in structure with that of the Great Kangaroo : 

 the glottis being widely open, and the chordae vocales very short and 

 rudimentary at the fore part of the ' rima.' 



The kidneys presented the usual simple conglobate structure. The 

 ureters passing through the vaginal loops terminate close together 

 14 lines from the communication of the urethra, or neck of the blad- 

 der, vdth the uro-genital canal. 



The ovaria, about 8 lines by 4 lines in size, presented a wrinkled 

 cerebriform surface. A cyst of near an inch in diameter was deve- 

 loped from the left ovary. The oviducts, about !§ inch in length, 

 terminate each in a subcompressed elongated uterus 1 inch by 

 3 lines. Each uterus opens by a distinct os tincae into the fundus 

 of a vagina, with a median cul-de-sac, extending 1 inch 3 lines be- 

 yond the commencement of the lateral bent vaginal canals. These 

 canals are about 3 inches in length : they presented a finely longitu- 

 dinally plicated inner surface, with a semilunar valvular fold 5 lines 

 before their termination in the uro-genital canal : the length of this 

 canal is 2 inches : it then opens, with the rectum, into a short and 

 wide common cloacal vestibule, closed by a strong sphincter muscle. 

 The lateral bent vaginal canals are shorter in proportion than in the 

 Macropus major : but the median vaginal cul-de-sac was closed, as 

 in that species. 



In a specimen of the Macropus Bennettii which I dissected in 1 845, 

 I detected a natural aperture of communication between the median 

 cul-de-sac and the urogenital canal. I had the pleasure of shovring the 

 specimen to Dr. Poelman, during a recent visit of that eminent Com- 

 parative Anatomist to the Hunterian Museum, and of thus confirming 

 the observation which he had, independently, made of a similar mo- 

 dification of the female generative organs in a specimen of the Ma- 

 cropus Bennettii dissected by him at the University of Gand*. 



The brain of the JDendrolagus inustus weighed 6 drachms. 



The cerebral lobes were smooth, and showed only a short Imear 

 indentation above the anterior part of each. There was no trace of 

 supra-ventricular commissure (corpus callosum), and in all particu- 

 lars save the more simple external surface the structure of the brain 

 corresponded with that of the Great Kangaroo as described in the 

 'Philosophical Transactions' for 1837. The proportion of the 

 weight of the brain to that of the body is as 1 to 230 ; in the Ma- 

 * Bulletin de I'Academie Royale de Belgique, torn, xviii. p. 599. 



