138 CLASS MAMMALIA. 



The ear is larger in the Egyptian species, and the fur 

 is shorter, and tufted. The fur of this nyctere is clear 

 brown above, and ash-colour underneath. In the nyctere 

 of Daubenton, the tints are almost the same, only that on 

 the back there is an approach to reddish, and to a dirty 

 white under the belly, where there is also a mixture of 

 fawn-colour. The Javanese species has the upper parts of 

 a bright red, and the lower of a reddish ash-colour. 



The nyctere, which was first described, had been brought 

 from Senegal, and we find that all the species inhabit the 

 warm countries of the old continent. 



It seems probable, that two species exist in Senegal. 

 Daubenton at least, has described two varieties, both of 

 which had been sent to him by Adanson. The second, 

 which, however, he established by a stuffed or dried speci- 

 men, differed from the first, in having the whitish-colour 

 of the lower part of the body mingled with an ashen-tint, 

 and in there being no reddish on the membrane of the 

 wings. The cranium, and principal bony parts of the same 

 individual, were inspected by M. Geoffroy St. Hilaire, and 

 they do not agree either in dimensions, or in some details of 

 form, with the nycteres of Daubenton, or the nyctere Thebais. 

 We shall now proceed to the Vespertiliones. This 

 name was employed, at first, to designate the small number 

 of bats which were known to the oldest systematic writers. 

 Brisson was the first who restrained its acceptation, and 

 applied it solely to such of these mammalia as have four 

 incisors in the upper jaw, and six below. This, naturalist, 

 as we have noticed before, established for the other spe- 

 cies of this family, a new genus, under the name of Ptero- 

 pus, to which he assigned this distinctive character : "In- 

 cisive teeth, to the number of four, in each jaw." 



Such was the classification to which Erxleben, in 1777, 

 seemed desirous to conform ; but as he wrote at an 

 epoch when the discoveries of Daubenton had considerably 



