CHIROPTERA 35 



As with the female, so with the male, there are three 

 classes, comprising that of the first autumn, which does not breed, 

 that of the second autumn, which probably breeds but rarely, and 

 that of the third and subsequent autumns, which is fully adult. 



Parturition was observed in a single case. The mother 

 had previously arranged herself with her head uppermost, and 

 the young one was born feet first and received in a cradle 

 formed by the maternal interfemoral membrane. The mother 

 severed the cord with her teeth. The whole process occupied a 

 period of slightly over half an hour. Thirty minutes later the 

 mother resumed her usual position with the head downwards, 

 and the young one occupied a position under her left wing with 

 the left nipple in its mouth. There it remained for eleven days, 

 after which it passed its time partly hanging by itself, partly 

 under the maternal wing. 



The young Mouse-ear at birth, despite the fact that the 

 wings are of late development in the embryo,^ has an expanse of 

 130 to 160 mm. It is almost naked, its colour blackish or 

 brownish above, but unpigmented beneath, the wings slightly 

 pigmented. The eyes are closed, the ears more or less reflexed. 

 The limbs are well developed, especially the claws, both of the 

 thumbs and feet, which are sharp and curved. The hooked and 

 trilobed teeth of the milk dentition arm the front of the jaws. 



It is with the claws that a young bat clings to its mother's 

 fur, holding on also by its teeth to the nipples, of which there 

 are a pair, specially long corrugated structures, placed pectorally.^ 

 So firm is the grip that a very young bat taken in the hand will 

 attach itself so firmly to the fingers as to be separated only by 

 vigorous shaking. The mothers have at first no difficulty in 

 carrying their young, which cling to them with the hind feet 

 buried in the fur of the abdomen, the thumbs clutching the 

 breast and neck, a nipple firmly fixed in the mouth. Some- 

 times during flight the young one bends downwards so that 



1 For an account of some embryos of bats, see Harrison Allen's paper in Con- 

 tributions from the Zoological Laboratory of the University of Pennsylvania, vol. i., 

 No. 2, 1895. 



2 Dobson {Catalogue of Chiroptera, 79 and 83) observed that in the males of some 

 fruit-eating bats the nipples are as large as in any female 'during lactation, and 

 suggested that, where two young are born at the same time, the male may relieve the 

 female of the charge of one. 



