170 THE NATURAL HISTORY REVIEW. 



up the numerous gaps in this branch of knowledge may materially 

 contribute to the promotion of science. 



So much for the Birds of India.. In our next number we hope 

 to be able to find space to discuss Dr. Griinther's volume on the 

 Eeptiles of the same country. 



XVI. — The Bats of North America. 



Monograph oe the Bats or North America. By H. Allen, M.D., 

 Assistant Surgeon, U. S. A. "Washington, Smithsonian Institution, 

 June, 1864. 



A few years since Professor Baird, the well-known Naturalist who 

 fills the office of Assistant Secretary in the Smithsonian Institution, 

 Washington, published the elaborate review of the Land-mammals 

 of North America, which forms the eighth volume of the Pacific 

 Bail way Be port.* Prom this review, which is very complete as re- 

 gards the greater part of the Mammal-fauna, the Chiroptera were 

 altogether omitted, as the materials then in hand did not appear to 

 be sufficient for the working out of this difficult group. This deficiency 

 in our knowledge of the Mammals of North America is now filled up 

 by the memoir of which we give the title above. Dr. Allen, its 

 author, is one of a number of young and rising naturalists who have 

 grown up under the auspices of the Smithsonian Institution — an 

 Institution, we may remind our readers, dedicated entirely to the ad- 

 vancement of human knowledge, an object which has been worthily 

 carried out by those to whom its direction has been entrusted. The 

 materials employed by Dr. Allen have been priQcipally the specimens 

 in the Museum of the Smithsonian Institution, to which the care of 

 the objects of Natural History, collected by the numerous exploring 

 expeditions sent out by the U. S. Government (each of them 

 invariably accompanied by a competent staff of professed naturalists) 

 is entrusted. The collections of the Philadelphia Academy of Sciences 

 and of the Museum of Comparative Geology of Cambridge have also 



* Reports of Explorations and Surveys, to ascertain the most practicable and 

 economical route for a railroad fi-om the INIississippi River to the Pacific Ocean. 

 Made under the direction of the Secretary at War in 1853-6. Vol. viii. Washing- 

 ton. 1857. 



