ORDER CHIROPTERA. 



H59 



-Lateral view of right dentition of the 

 Mole {Talpa europeea). Enlarged. 



Family Adiposoricid^e. — This family contains the minute Adipo- 

 sorex and Adiposoriculus, from the Lowest Eocene of Rheims, which 

 Dr Schlosser regards as related to the Shrews, but forming a distinct 

 family, attaining a higher degree of development. 



Family Leptictid^e (Ictopsid^e). — The second section of the 

 Insectivora Vera includes the recent families Potamogalidce, Soleno- 

 dontidce, Centetidce, and Chrysochloridce ; and we may provisionally 

 place in the same neighbour- 

 hood the family Leptictida of 

 the North American Eocene 

 and Miocene. The latter 

 forms are regarded by Dr 

 Schlosser as true Insectivora, 

 although they were placed 

 by Professor Cope near the 

 Hycenodontidtz. The family 

 includes the genera Leptictis, 

 Mesodectes, Ictops, and per- 

 haps Geolabis. 



Finally the names Cente- 

 todon, Entomodon, Entomacodon, Centracodon, and others have been 

 applied to the remains of small entomophagous mammals from the 

 Lower Tertiaries, of which the serial position is doubtful. 



Order X. Chiroptera. — The Chiroptera are characterised by 

 the fact that the anterior limbs are longer than the posterior, the 

 digits of the fore limb, with the exception of the pollex, being enor- 

 mously elongated (fig. 1344). These elongated fingers are united 

 by an expanded membrane or patagium, which is also extended 

 between the fore and hind limbs and the sides of the body, and in 

 many cases passes also between the hind limbs and the tail. The 

 patagium thus formed is naked, or nearly so, on both sides, and 

 serves for flight. In the manus the pollex, and sometimes the next 

 digit as well, is unguiculate, or furnished with a claw ; but the other 

 digits are destitute of nails. In the hind limbs all the toes are 

 unguiculate, and the hallux is not in any respect different from 

 the other digits. AVell-developed clavicles are always present, and 

 the radius has no power of rotation upon the ulna. The four 

 kinds of teeth are always present (although the molars are aborted 

 in Desmodus), and the dental formula is never known to exceed 



/ 



C. -, Pm. 5 M. k 



* 3 3 



This order, which is evidently a branch from the Insectivorous 

 stock, is divided into the suborders Megachiroptera and Micro- 

 chiroptera. The former, which is characterised by the possession 

 of smooth cheek-teeth, marked by a longitudinal groove, comprises 



