180 



CHIROPTERA 



rounded off above, its inner margin not continuous with posterior 

 border of conch. Tragus about half as high as conch, its form 

 essentially as in M. mystacinus though a little more slender 

 (greatest width contained nearly three times in height of 

 anterior border) ; basal lobe small but well developed. Wing 

 essentially as in M. mystacinus; third, fourth and fifth meta- 

 carpals sub-equal, falling short of elbow by about 5 mm. ; 

 membrane inserted at base of outer toe. Calcar and free border 

 of interfemoral membrane as in M. mystacinus. Tail shorter 

 than head and body (laid forward it extends to middle of crown), 

 the terminal vertebra free. 



Fur and colour. — Quality and distribution of fur as in Myotis 

 mystacinus and M. nattereri. Upper parts uniform wood-brown 

 with a slight tinge of umber, the exact shade almost impossible 

 to describe exactly ; underparts a buffy grey in strong contrast, 

 irregularly clouded by the slaty brown of underfur ; ears and 

 membranes an indefinite dark brown. 



Skull. — In general aspect the skull resembles that of Myotis 

 myotis, due allowance being made for its much smaller size, since 

 it is much more slender than in any of the other small species ; 

 breadth of bi - ain-case equal to about one-half distance from 

 lambda to posterior border of narial emargination. Dorsal 

 profile rising gradually above rostrum and forming a strong 

 convexity over anterior portion of brain-case, behind which it is 

 essentially flat to lambda ; ventral profile nearly flat, slightly 

 elevated posteriorly ; occipital region slightly projecting, just 

 sufficiently to conceal condyles when viewed from above. Brain- 

 case ovate, noticeably wider than rostrum ; sagittal crest low but 

 evident ; lambdoid crest moderately developed at sides, obsolete 

 at middle ; greatest depth of brain-case about two-thirds mastoid 

 breadth ; floor of brain-case with obscurely defined lateral grooves. 

 Interorbital region not evidently hour-glass shaped, owing to the 

 slight widening at lachrymal level ; anterior upper border of 

 orbit slightly ridged. Rostrum slender, widening a little at 

 anterior extremity, the dorsal surface smoothly rounded off at 

 sides, though with indication of a slightly developed median 

 groove ; narial emargination narrow but deep, extending back 

 about half way to level of anterior rim of orbit ; rostral depth 

 at front of orbit about equal to distance from orbit to middle of 

 canine ; palate long and narrow as compared with that of the 

 other small species, both transverse and lateral concavities evident, 

 especially just behind middle ; anterior emargination rather large, 

 sub-circular in general outline, extending back about to level of 

 space between canine and first premolar ; posterior extension of 

 palate about as broad as long ; interpterygoid space wider than 

 long, encroached on by blunt median palatal spine. Mandible 

 essentially as in Myotis myotis, the coronoid process higher and 

 with more oblique posterior border than in the other small species. 



Teeth. — The teeth are rather small relatively to size of skulh 



