494 Proceedings of the Royal Irish Academy. 
may Ibe entirely dispensed with in small animals, such as rabbits, 
hedgehogs, &c., &c., with which I have found the instrument exhi- 
bited to work most efficiently. 
The upper part of the apparatus is fixed underneath the operating 
table by three strong cords, as seen in fig. 2, the inferior part is like- 
wise fixed by cords to one end of a piece of wood, about 1 6 inches 
long by 4 broad and f thick. The other end of this board is hinged 
to the floor, and thus acts as a treadle. Of course when the bellows 
is closed, the end of the treadle to which it is attached should be 
raised from the floor sufficiently to allow the complete expansion of 
the bellows when the treadle is depressed. 
XLII.— The Anatomy op Ch^ropsis Libertensis. By Alexander 
Macaxister, M. B., M. B. I. a., Professor of Comparative Anatomy 
in the University of Dublin. (With Plate XXYIII., Science.) 
[Read June 9, 1873.] 
In 1844, Mr. S. Gr. Morton published in the Proceedings of the Aca- 
demy of Natural Sciences of Philadelphia (vol. ii., p. 14), an account 
of the bones of a small species of hippopotamus brought by Dr. 
Goheen, of Monrovia, which he named H. minor. These bones (two 
skulls) had been procured on the banks of the St. Paul Biver, Liberia. 
The name Hippopotamus minor being preoccupied by one of Cuvier's 
fossil species, Mr. Morton later (Journal of the same Academy, second 
series, vol. i., 1849), substituted H. Liberiensis, for the new small 
form. A second and more detailed description at the hands of Pro- 
fessor Leidy led to the founding by that comparative anatomist of a 
new genus for its reception, which he at first called Chaerodes (pre- 
occupied in another department) and finally Chaeropsis. This creature 
has more recently (1867), received another name from the late Pro- 
fessor Gratiolet, Ditomeodon, which, however, being subsequent to 
Cheeropsis, must be abandoned. M. Alphonse Milne Edwards having 
obtained from Prince JN'apoleon a skin, a skeleton, and two skulls of 
this species, has written thereon a monograph (Becherches pour servir 
a I'Histoire I^aturelle des Mammiferes, Livraison 2, 1868). 
The present specimen was found by a native hunter in Liberia, by 
whom its mother was shot. It was supposed to be one or two weeks 
old. On its being brought alive to Governor Pope Hennessy, he kindly 
directed that it should be transmitted to the Dublin Zoological Gar- 
dens, in the care of Dr. Price. Unfortunately on its arrival in 
Liverpool the animal caught cold, which caused violent inflammation 
of both lungs, and in spite of the care taken of it she did not survive 
her arrival in the gardens by five minutes. By this time she was 
supposed to be eight weeks old, and her dimensions are as follow: — 
