18S(i.] MAMMALS IN THE SOCIK,Ty's GARDENS. 215 



atlas had become firmly aiikylosed to the occiput, and it is very 

 curious that the animal could have survived so serious au accident. 



A somewhat similar case came under observation in an Ichneu- 

 mon. In this instance the atlas had bet-n dislocated from its rela- 

 tions to the occiput and axis, so as to occupy the situation shown in 

 the accompanying drawing (tig. 7). In this instance the animal 

 must have survived the injury a long time, because the occiput and 

 atlas are firmly united by new bone. 



Concretions formed of insoluble or indigestible matters are of 

 frequent occurrence in the alimentary canal of Horses and Cattle, and 

 at times may attiiui to very large size without causing any incon- 

 venience. This is more particularly the case when these segropiles, 

 as they are termed, occur in the caecum of horses. In this situation 

 they have been known to weigh more than fifty pounds. These 

 heavier masses are composed of magnesium phosphates ; the lighter 

 ones consist of hair which the animal licks from its body. This 

 form is fairly frequent in calves, and I have met with a specimen in 

 a Hyaena. Concretions of insoluble substances, such as magnesia, 

 pius, seeds, &c., occur also in the human subject. Recently a Tiger 

 died in the Gardens, and its bowels were found empty until the 

 rectum was reached. Here a large mass of solid material was found 

 about two inches from the anus, measuring six inches in length and 

 eight inches in girth, covered with mucus. The lower end was 

 bluntly pointed, and had caused by its pressure ulceration of the 

 mucous membrane. The rectum was mucli dilated. On breaking 

 into the mass it was found to be composed entirely of sawdust, 

 which the animal had licked from the floor ot the cage. A cast of the 

 abnormal mass was taken at the time by the assistant, Mr. Ockenden. 

 During the past four or five years there is one fact more than any 

 other which has impressed me in the course of my work at the 

 Gardens, and that is the infrequency of neoplasms. In the many 

 hundreds of animals coming under observation, a tumour has been 

 a rarity, and this applies with still greater force to cancers. The 

 only example of this terrible malady I have seen in tvild animals 

 was a medullary cancer in the viscera of a Python. The infrequency 

 of these growths makes the following case additionally interesting. 



A Short-headed Phalanger, Belideus breviceps, was found to have 

 a large, hard nodular mass in its marsupium. On slitting open the 

 pouch a tumour presented itself, having the appearance represented in 

 fig. 8, p. 216. Microscopically it presented all the characters peculiar 

 to scirrhous cancer as seen in the human subject — that is, there were 

 alveolar spaces enclosing masses of cells. The alveolar walls were 

 composed of dense fibrous tissue. The structural details of the 

 growth coincided with that of the gland from which it originated, 

 except that the cells, instead of clothing the walls of the alveoli in a 

 regular manner, were tumbled in confusion into the interior. This 

 case is, so far as I know, the first authentic example of cancer in a 

 marsupial. 



The last specimen on my list is perhaps as interesting as any. It 

 is an intussusception of the ileum into the caecum, through, but not 



