MINIOPTERUS 



271 



at outer side of each pit ; auditory bulla moderately large, the 

 transverse diameter about equal to distance between bullte. 

 Interorbital region moderately constricted, slightly hour-glass 

 shaped, the lachrymal region scarcely more than half as wide 

 as brain-case, smoothly rounded at sides ; rostrum tapering 

 gradually, rounded off at sides, flattened concave along median 

 lihe, the narial emargination small, squarish, extending backward 

 about one-third of the distance to front of forehead ; rostral 

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

 outer incisor ; anteorbital foramen rather large, directly above 

 small premolar, the anteorbital canal half as long as rostrum, 

 thus much longer than in any other European bat ; lachrymal 

 foramen just outside of orbit, on level with upper border of 

 anteorbital foramen. Palate long and wide, distinctly concave 

 both laterally and longitudinally, terminating rather abruptly a 

 little behind level of last molar, a small but evident foramen at 

 each side near posterior edge ; median spine large ; mesoptery- 

 goid space squarish, slightly wider posteriorly than anteriorly, 

 the short hamulars bent inward. Mandible slender, a little 

 deeper at symphysis than behind tootli-i'ow, the posterior seg- 

 ment unusually small, with nearly horizontal, slightly concave 

 upper border ; angular process relatively long, expanded at 

 outer end. 



Teeth. — Relatively to size of skull the teeth are small and weak. 

 Inner upper incisor low, the crown very oblique, with postero- 

 external concavity and small postero-internal cusp ; outer upper 

 incisor considerably larger than inner, the crown flattened in 

 axis of tooth-row, the width of its flattened-concave posterior 

 surface about half its height, that of its outer border scarcely 

 one-fifth height, cingulum obsolete, but forming a minute postero- 

 external cusp ; the two teeth lie in curve of anterior portion of 

 tooth-row, and the outer is separated from canine by a space 

 about equal to its greatest diameter. Lower incisors closely 

 crowded but not imbricated^ the crown-area increasing regularly 

 from first to third, the outline of the row as a whole broadly 

 V-shaped ; «\ and i.^ with crown very low, the cutting edge 

 obscurely tritid, the crown of each tooth wider posteriorly (in line 

 of tooth-row) than anteriorly, but this more evident in second 

 than in first ; i\ nearly terete, the middle and posterior cusps 

 enlarged and separated by a deep groove, the anterior cusp 

 reduced to a mere rudiment. Upper canine slender and weak, 

 sub-terete, but distinctly flattened on inner side, the shaft with 

 distinct anterior and posterior longitudinal grooves but without 

 well developed cutting edge, the cingulum narrow, complete, 

 but without cusps ; lower canine scarcely higher than main 

 cusps of molars, its inner and posterior surfaces flattened, its 

 antero-external surface smoothly rounded, cingulum forming a 

 low but evident antei'o-internal cusp. Anterior upper premolar 

 with crown area about equal to that of canine, its general form 



