THE FAMILIES AND GENERA OF BATS. 
209 
m 2 with hypocone always indicated arid in some species well de- 
veloped, a distinct concavity between it and protocone ; m 3 variable 
in form, usually with well developed metacone and three commis- 
sures in the smaller species, but with metacone and third commis- 
sure obsolete in the larger forms; lower molars with all the cusps 
present and of normal form. Skull not essentially different from 
that of Pipistrellus , the rostrum flattish or more usually rounded 
off above, the nares and palatal emargination not specially enlarged, 
the latter at least as deep as wide. Externally as in the related 
genera. 
Species examined. — Eptesicus capensis (Smith) and related forms, 
E. serotinus (Schreber), E. platyops (Thomas), E. megalurus (Tem- 
minck), E. matroka (Thomas and Schwann), E. rendalli Thomas, 
E. hillarii (Geoffroy), E. dorianus (Dobson), E. minutus (Tem- 
minck), E. matschiei Thomas, E. tenuipinnis (Peters), E. nilssoni 
(Keyserling and Blasius), E. fuseus (Beauvois) and related forms. 
Remarks. — Notwithstanding the great difference in size between 
such species as Eptesicus pachyomus and E. pumilus , the characters 
of the genus are very constant. In the smaller forms the skull is 
more slender and Myotis-Wkz and the last upper molar is better de- 
veloped, while in the larger species the skull is more angular. 
Genus VESPERTILIO Linnaeus. 
1758. Vespertilio Linnaeus, Syst. Nat., I, 10th ed., p. 31 ( murinus ). 
1839. Vesperugo Keyserling and Blasius, Wiegmann’s Archiv. fur Natur- 
geschichte, 5ter Jahrg., I, p. 312 (part). 
1839. Vesperus Keyserling and Blasius, Wiegmann’s Archiv. fur Natur- 
geschichte, 5ter Jahrg., I, p. 313. Subgenus of Vesperugo (part). 
1856. Meteor us Ivolenati, Allgem. deutsch. naturhist, Zeitung, Dresden, 
neue Folge, II, p. 131 (part; included nilssoni, “discolor ”=murinus, 
savii, leucippe, and aristippe). 
1863. “ Aristippe Kolenati, Beitrage zur Kenntniss der Phthiriomyiarien, 
Petersburg, 1863” (part: included both murinus and nilssoni). 
1872. Marsipolcemus Peters, Monatsber. k. preuss. Akad. Wissensch., Ber- 
lin, p. 260 (subgenus of Vesperugo for albigularis=murinus) . 
1878. Vesperus Dobson, Catal. Chiropt. Brit. Mus., p. 183 (subgenus of 
Vesperugo), part. 
1897. Vespertilio Miller, Ann. and Mag. Nat. Hist., 6th ser., XX, p. 384. 
October, 1897 (part). 
1897. Vespertilio Miller, North American Fauna, No. 13, p. 95, October 
16, 1897 (part). 
1900. Vespertilio Mehely, Monogra. Chiropt. Hungarise, p. 219 (part: in- 
cluded both murinus and “ borealis ”=nilssoni) . 
T ype-species. — V espertilio murinus Linnaeus. 
Geographic distribution. — Northern portions of Europe and Asia. 
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