38 MAMMALIA ORDER ILCHIROPTERA. 



stance that these latter are so fixed in the jaw as to diverge from one another, 

 as well as by the cheek-teeth (that is to say premolars, and molars together) 

 forming three pairs in each jaw. A further distinctive feature is to be found 

 in the minute size of the second upper premolar tooth, while the ear has a 

 characteristic elongated oval form, and its inner tragtis is remarkably narrow. 

 The genus has a wide geographical distribution, being spread over the tem- 

 perate and tropical regions of both hemispheres. A bat belonging to this 

 genus (F. welivitschi) from West Africa, closely allied to the British Bechstein's 

 bat (F. bechsteini}, is remarkable for the circumstance that the wing-membranes 

 are coloured orange and black; the Indian F. hodyamii also having a very 

 similar type of coloration. Another Indian bat with black and orange wings 

 belongs to the genus Cerivoula, distinguished from Vespertilio by the upper 

 incisor teeth being vertical instead of divergent. A fourth peculiarly coloured 

 species is the West African Nycticejus albofuscus, belonging to a genus closely 

 allied to Vesperugo, and having the outer portions of the wing-membranes 

 dazzling white. In these abnormally coloured bats it appears that those in 

 which black and orange obtain are in the habit of reposing among the fruit 

 and leaves of various tropical trees, in which an orange ground is frequently 

 relieved by black spots. 



Schreibers' bat (Miniopterus schreibersi), ranging from Germany to Japan 

 and Australia, is the only member of a genus differing from all those hitherto 

 noticed by the great elevation of the crown of the head above the face ; the 

 same feature also characterises the South American and West Indian 

 bats forming the genus Natalus. Two very curious bats belonging to this 

 family, and each forming a genus by itself, are remarkable for having 

 the feet furnished with adhesive discs, by which they are enabled to climb 

 smooth, polished surfaces. One of these is the tricolor bat (Thyroptera 

 tricolor) of Brazil, in which the suckers form circular discs on the lower 

 surface of the thumb and the sole of the hind-foot ; the second being the 

 golden bat (Myxopoda aurita) of Madagascar, in which the sucker on the 

 thumb is in the form of a horse-shoe, while those on the feet are of smaller 

 size. Both these bats are distinguished from all the other members of the 

 family by having three joints to the Miird or middle finger of the wing, 

 thereby resembling the undermentioned family Phyllostomatidce. 



In the preceding families of the Microchiroptera the tail is enclosed in the 

 membrane connecting the two hind-legs, but in the two families of this group 

 still remaining for consideration, this appendage, when pre- 

 Free-tailed Bats, sent, generally either perforates the membrane in such a 

 Family manner that its free extremity appears on the upper extrem- 

 Emballonuridce. ity of the latter, or is produced considerably beyond the free 

 hinder margin of the same. Another feature is that- the 

 inner, and frequently the only, pair of upper incisor teeth, are of large size 

 and placed close together in the middle line ; and a third characteristic is to 

 be found in the circumstance that when the wing is at rest, the first joint of 

 the third finger is folded back upon the supporting metacarpal bone instead 

 of being extended forwards in the same line. In two species, each repre- 

 senting a genus by itself, the last-named characteristic is, however, wanting. 

 Only a single species cf these two families is met with in Europe, the second 

 family being exclusively American. In the members of the family Em- 

 ballonundce there are but two joints in the third finger of the wing, and 

 there is no distinct nose-leaf ; but, as a rule, the ear is furnished with a 

 small inner tragus, and there is but a single pair of upper incisor teeth, 



