274 Bibliographical Notices. 
books so beautifully ulustrated. The author’s method has the merit 
of inaugurating a comparison of the minute anatomy of the nervous 
system by enabling the reader to see the structures which he has — 
discovered as he saw them; and hence the book will always be a 
valuable work of reference; and it will certainly induce others to 
hand on the torch of knowledge in a like excellent way. 
Memoirs of the Geological Survey of India. Paleontologia Indica, 
being Iigures and Descriptions of the Organic Remains procured 
during the progress of the Geological Survey of India. Published 
by order of his Excellency the Governor-General of India in 
Council. Series x. Indian Tertiary and post-Tertiary Verte- 
brata. Vol. U1. Part 1. Siwalik Rhinocerotide. Part 2. Sup- 
plement to Siwalik and Narbada Proboscidia, with 11 plates: 
1881. Part 3. Siwalik and Narbada Hquide, with 5 plates : 
1882. Part 4. Siwalik Camelopardalide, with 7 plates: 1883. 
Part 5. Sewalik Selenodont Suina &c., with 3 plates: 1883. By 
R. Lyprxxer, B.A., F.Z.8., Geological Survey of India. Calcutta: 
the Geological Survey Office. London: Triibner & Co. 
Tue five parts published of the second volume of the Indian Ter- 
tiary Vertebrata are all by Mr. Lydekker, and devoted to Siwalik — 
fossils. The volume will apparently include other parts, but already 
extends to 176 pages and 25 plates. There is no reason for the 
association of the parts in the way in which they are issued, and 
every part has a separate pagination as well as the pagination of 
the volume; the plates take the numbering for the volume only. 
On account of the wealth of material and interest of the types de- 
scribed, this work will always be important in paleontology ; and we 
cannot help believing that its value is enhanced by the manner of 
dealing with the systematic part of the subject which the author 
has adopted, for the aims of science are certainly better served by 
making genera large and then showing the characters wherein the 
species differ from each other, than by adopting the too common 
method of subdividing genera till the evidences of their mutual — 
dependence and of the evolution of species are obscured. If any one 
should observe that the author has not always adhered to so excel- 
lent a plan, it must be conceded that when the materials are scanty 
and the types such that their true nature cannot be worked out, 
then it becomes permissible to formulate whatever knowledge is avail- 
able by a nomenclature which shall not prejudge affinities. 
It is almost impossible to separate the fossil forms of rhinoceros — 
from those which still live. Dr. Falconer detected the hornless 
rhinoceros, which he named <Acerotherium perimense, and to this 
species Mr. Lydekker now refers the Rhinoceros planidens and R. 
iravadicus, which he has defined in the former volume: the teeth 
approach those of the rhmoceroses of Sumatra and Java. ‘This is 
the only occurrence of Acerothertum in the Siwalik beds, ‘The other 
