146 VESPERTILIONID^— MYOTIS 



Description: — In general form and appearance this bat is typical 

 of the group Leuconoe. In size it is somewhat larger than Pipistrellus 

 pipistrellus, but distinctly smaller than Nyctalus leisleri. 



The ear (Fig. 2, No. 5, p. 7), when laid forward, reaches about to the 

 nostril ; the outer margin is very slightly notched, the upper two-thirds 

 being straight or only slightly concave, the lower third abruptly convex ; 

 a deep emargination opposite the base of the tragus gives rise to a 

 distinctly rounded basal lobe; the inner margin is convex almost 

 throughout its length, most markedly at its centre, whence it passes 

 upwards to a broadly rounded tip ; there are four cross-folds. 



The tragus, which is about half as long as the ear, reaches its greatest 

 breadth at about its centre, is straight, and not sickle-shaped, and tapers 

 to a more or less acute point ; the inner margin is about straight, the 

 outer gently convex, with a distinctly rounded triangular lobe projecting 

 just above the base. 



In the -wing (Plate VII., Fig. 3, p. 86) the most noticeable features 

 are the extremely long lower leg and large foot ; a well-developed spur 

 or calcar extends fully three-quarters of the distance from the ankle to 

 the tail, the tip of the spur projecting from the posterior border of the 

 interfemoral membrane as a small, but distinct, lobe. The third digit is 

 short, so that the wing as a whole is of less than average length. The 

 wing-breadth is moderate, the fifth metacarpal being distinctly shorter 

 than the third. The tail is short, and has usually two free vertebrae. 



The fur is short, but soft and plentiful. The hairs on the ear are 

 small and inconspicuous. The face is half-naked and rather tumid before 

 the nostrils, but the muzzle carries a moustache composed of numerous 

 long hairs (Plate XI., Fig. 2, p. 140). Both surfaces of the wing are furred 

 as far as a line running from the centre of the humerus to sHghtly below 

 the head of the lower leg ; the upper surface and the posterior border 

 of the interfemoral are ciliated, the latter inconspicuously. The toes are 

 provided with whitish hairs. 



The colour above is warm brown, of some shade between "mars 

 brown " and " mummy brown," the bases of the hairs darker and the 

 tips lighter, resulting in a grizzled appearance ; below, near light 

 "broccoli brown," the hairs plentifully tipped with dirty white, or 

 yellowish. The line of demarcation is moderately distinct, and runs 

 approximately from the angle of the mouth to the thigh. The wing is 

 dusky, with a reddish tinge, the interfemoral membrane whitish beneath. 

 I have had no series from which to study variation, seasonal or 

 otherwise, but the general colour is somewhat variable, perhaps owing to 

 age ; the young are sometimes described as darker (Bell, Millais), some- 

 times as greyer (Coward and Oldham). Jenyns' description of Vesper- 

 tilio csdilis was based on an albino specimen. 



In the skull (Fig. 8, No. 2, p. loi) the profile of the cranium is almost 



