MYOTIS 175 



Fur and colour. — Quality and distribution of fur essentially as 

 in M. mystacinus, but free border of interfemoral membrane 

 distinctly though not very densely fringed with hairs about 



I mm. long. Colour of upper parts a lighter and less yellowish 

 brown than in M. mystacinus, the exact shade intermediate 

 between the wood-brown and broccoli-brown of Ridgway, the 

 longer hairs with faintly darker tips visible in certain lights ; 

 underparts rather sharply contrasted whitish buffy grey ; a well 

 defined line of demarcation extending from shoulder to base of 

 ear ; basal portion of hairs clove-brown ; muzzle and cheeks dusky, 

 but not so dark as in M. mystacinus ; ears and membranes dark 

 brown. 



Skull. — In all its dimensions the skull is appreciably larger 

 than that of Myotis mystacinus. In general form it is slightly 

 less slender. Forehead rising more abruptly but occipital region 

 not higher than main portion of brain-case, so that dorsal profile 

 shows a stronger concavity in interorbital region than that of 

 M. mystacinus, while over greater extent of brain-case it is 

 essentially flat, or slightly falling away posteriorly, instead of 

 rising by two well defined curves to lambdal region. Posterior 

 palatal region about as in M. mystacinus, except that mesopterygoid 

 space extends further forward, and median spine is better 

 developed. Auditory bulla relatively smaller than in M. mysta- 

 cinus, its greatest diameter decidedly less than distance between 

 bullae. 



Teeth. — In general the teeth resemble those of Myotis 

 mystacinus apart from their greater size. They differ, however, 

 in certain details of form : crown area of outer upper incisor 

 appreciably greater than that of inner tooth ; angle at front of 

 lower incisor row wider, though evident ; upper canine relatively 

 weaker, its posterior cutting edge less developed, the cross section 

 of its shaft half-terete owing to the obsolescence of postero- 

 external and anterior longitudinal furrow ; lower canine with 

 length of base much greater in proportion to height of shaft, and 

 cingulum more oblique ; second upper premolar nearly equal to 

 first in cross section ; crown area of large premolar not so great 

 relatively to that of first molar, the cusps on inner border 

 obsolete or absent ; lower premolars with less slender crowns, 

 the cingulum of the third forming a very low, sometimes obsolete 

 antero-internal cusp ; molars, especially m 3 , with narrower 

 crowns. 



Measurements. — External measurements of adult male from 

 Colpin, Brandenburg, Germany, and adult male from Magdeburg, 

 Germany: head and body, 50, 44; tail, 41, 40; tibia, 17, 16; 

 foot, 8- -2, 9-0; forearm, 39-2, 40-2; thumb, 7-0, 6-2; third 

 finger, 71,71; fifth finger, 56, 56 ; ear from meatus, 18, 18 ; tragus, 



I I • 0, 1 1 • 2. Two adult females from Spain (No. 94. 1 . 1. 8, Seville, 

 and No. 8. 7. 23. 4 from Bellver, Lerida, paratype of M. escalerai) : 

 head and body, 46, 46 ; tail, 41, 43 ; tibia, 15, 17 ; foot, 7 ■ 6, 9 • 2 ; 



