1865.] The Bats of North America. 549 



bably the agents for augmenting the sense of touch alone, and in this 

 way act conjointly with the wing membranes, in which the sense of 

 touch chiefly resides, and in which the papillae of touch are extensively 

 distributed. This function is, in many places, aided by the delicate 

 hairs which are sparsely distributed upon the under-surface of the 

 membranes. 



The subjects of this monograph are animals which have scarcely 

 met with their due share of attention, not that they are undeserving 

 of notice, for few orders are more interesting ; but their crepuscular 

 and nocturnal habits render them difficult of observation. This fact 

 is well illustrated by the history of British Bats. Gilbert White 

 remarked in his day, " At present I know only two species of bats, 

 the common V. murinus (the Vespertilio pipistrellus of recent 

 authors), and V. (Plecotus) auribus." He ^himself added a third 

 species to the list, and his editor, in 1835, enumerates seven species. 

 In Bell's ' History of British Quadrupeds,' seventeen species are 

 described, and others have since been recognized as inhabiting this 

 country. It is worthy of remark, however, that of the seventeen 

 species described by Bell, seven or eight have as yet only been 

 represented by a single specimen, or taken in a single locality, a 

 sufficient proof that we are in comparative ignorance of these animals ; 

 and that further research will infallibly be rewarded by the discovery 

 of additional species. 



The habits also of the known species are very imperfectly under- 

 stood. The inaccessibility and dismal situation of their retreats, 

 render it matter of great difficulty to secure them while hibernating ; 

 and it is only by sheer accident that they have been found under these 

 circumstances. Opportunities, however, are occasionally offered to 

 observe their flight and their habits of repose, by their accidental 

 entrance into the open apartments of dwellings in warm weather, 

 when they are readily caught, though they do not bear captivity well. 

 They will then eat raw meat with avidity, but, curiously enough, 

 refuse to partake of insects. They also lap up water eagerly ; in 

 fact, the first act of a bat, after emerging in the evening from his 

 retreat, is to fly to the water. 



The numerous parasites which infest bats constitute, perhaps, 

 the most revolting feature in the history of these creatures. The 

 enormous population of acari found upon their bodies is due to the 

 great generation of animal heat in their close haunts, a condition con- 

 ducive to the rapid increase of all kinds of vermin. In America the 

 common bed-bug (Cimex lectularius) is frequently found upon their fur, 

 and this is believed to be the cause of the introduction of this pest, in 

 many instances, into homesteads from which general cleanliness would 

 otherwise banish them. The immense number of some species may 

 be judged from the fact that in a dismantled and uninhabited house 

 in Maryland, there were found, when it came to be once more 

 tenanted, myriads of a small black species of bat, which issued forth 

 in clouds at the cry of the whip-poor-will to feed upon gnats and 

 mosquitoes. Measures having been taken to rid the place of the 

 pest, it was found by actual counting that nine thousand, six hundred 



