A MONOGRAPH OF THE BATS OF NORTH AMERICA. Il7 



without locality) the central incisor was not biM. Canine with a nar- 

 row posterior concave service; it is deflected a little outward so as to 

 I)erinit the flange between it and the palatal surface to lie in the axis 

 of the tooth row. The palatal surface remarkable for a narrow column- 

 like longitudinal ridge at the flange deliuing the surfa(;e anteriorly. 

 The single premolar not distinctive; it lies in contact with the canine; 

 in this regard it differs from the arrangement in A. velatus, where an 

 interval is defined. The first molar with the first V-shaped figure is 

 much smaller than the second; the protocone exhibits an occasional 

 crenulated appearance posteriorly. In the second molar the V's are 

 equal. In the third molar the protocone is simple entire, the heel ab- 

 sent; in this tooth the posterior limb of the first V equals one-half the 

 length of the anterior, while the second V is represented only by the 

 initial half of the anterior limb. 



Mandibidar teeth. — lucisors equal, crowded, all possessing trifld cut- 

 ting edges, the third being slightly thickened, and in some individuals 

 the trifid figure obscure. Canine with deep, broad, concave posterior 

 surface, small lingual surface — the two being separated by a laminate 

 flange; a prominent posterior cusp lies on the lingual side. The first 

 premolar is smaller than the second, and is wedged in by the basal 

 cusps of the canine and the premolar. The molars quite as in VespertUio, 

 i. e., with sharply acute cusps, especially prominent hypoconid, and 

 small cuspule in posterior borders. 



Notes on the skeleton. — The coracoid process of scapula, with a small 

 anterior spine from the free end — none from the posterior. The ex- 

 ternal tuberosity of humerus slightly higher than the internal trochlear 

 spine; small nodular, and looks directly backward. The oblique keel 

 on articular surface wider than the grooves. The outer groove is much 

 the narrower and confined to anterior and axial parts, i. e., is absent 

 posteriorly. The articular surface one-third wider internally than ex- 

 ternally. The proximal rudiment of ulna not anchjdosed to the radius. 

 The slender thread-like shaft lies against the radius at its middle, but 

 not joined to it. It ends in fibrous tissue, and is gradually lost near 

 the wrist. The distal ulna rudiment is (piadrate and perforate. Kumber 

 of ribs, eleven. 



Habits and distribution. — The brown bat is probably the most com- 

 mon species of any in the United States. The red bat and the little 

 brown bat appear to be numerous in collections, and are more likely 

 to be gathered in large numbers in some localities than is the brown 

 bat. But on the whole the brown bat is the one most generally met 

 with. It frequents not only the open country but the towns. It often 

 enters our apartments at night in search of a resting place, and not for 

 food, as is often surmised. According to C. Hart IMeriiani (Mammals 

 of the Adirondack Region, 1886) it is rare in the mountainous tracts 

 of northern New York, and it is believed that the species may be, in 

 the main, a dweller in the warmer low ranges. The highest latitude 



