A MONOGRAPH OF THE BATS OF NORTH AMERICA. 163 



Geuns NYCTINOMUS Geoffroy. 



iVyc<i«oniM8 Geoffroy, Descript. de 1' Egypte, ii 1812, 114; H.Allen, Monog. N. A. 

 Bats, 1864,5; DobsoD, Cat. Chirop. Brit. Mas., 1878,437; Alstou, Biolog. Ccu- 

 trali-Amer., Mamui., 1879-82, 33. 



Thisseuus is in close relation with Molossus. It is distiiiiiuislied by 

 the absence of uiiiou of the palatal plates of the preniaxilla. Teeth 

 Avith large hyi)ocoue. Auricle with internal basal ridge, developed 

 into a well defined ''keel;" the external basal ridge continuous with 

 an erect external basal lobe. Auricle quadrate; inetacarpo ]>halangeal 

 joint of third and fourth digits mobile, bent forward; the interpha- 

 langeal joint of the same digits mobile, bent backward (these digits 

 when extended reach far below the level of the toes); the joints of the 

 fifth digit rigid and in line Avith the metacarpal. The secoiul meta- 

 carpal lies palmad to the third; the phalanx is rudimental or absent. 



Xijctinomus is of wide distribution, examples being found in all parts 

 of subtropical and tropical regions. With the exception of N. nor- 

 folcensis {AnstTnlin, Norfolk Island) and j\".jo/<ore«6'/6- (Malay Penin- 

 sula), the species are singularly alike in essential features. A critical 

 examination of all the species is demanded before the exact jjosition 

 of the ii"orth American forms can be determined. 



The ISTorth American species considered in the following pages are 

 iV. hrasiliensis and JSF. macrotis. I have not seen iV. fcmorosaccus 

 Merriam (N, A. Fauna, No. 2, 1889, p. 23), or N. mohavensi.s, jNIerriivm 

 (N. A. Fauna, No. 2, 1889, p. 23), both from southern California. (See 

 Appendix. 



1. Nyctinomus brasiliensis Isid. Geoffroy. (Plates xxxii, xxxiii.) 



Mo1ossi(.s nasuttts .Spix, Sim. et Vesi). Bras., 1823, 60, pi. xxxv, lig. 7; _/((/«; Isis, 

 August, 1824, 899 (Brazil); Schinz, Syu. Mam. i, 1844, 143. 



Di/sopes nastitiis Tomminck, Mon. Mam. i, 1827, 234. lb., Zoiil. .lour., in, 1828, 459; 

 Wagner, Sehreb., Siiugetb., Suppl. i, 1844, 474; ih. V, 1855, 711. 



nished with a palmar tubercle, and the coracoid process is always bifid, the posterior 

 portion being prolonged. 



A large spheno-palatiut^ foramen is ])resont. while the presence of jjahital processes 

 to the premaxilhe is detected in most of the genera. The tail is always i)roduce(l well 

 beyond the interfemoral meml)rane, aud the accessory cartilage is absent from the 

 short, rigid fifth digit. 



The groups of the Molossi constitute a subfamily characterized by tht; narrow wing, 

 prominent thumb, free terete tail, and the rigidity of the short fifth digit. The 

 group at one end recalls the subfamily Emballanurinte in the dorsal flexion and ad- 

 duction of the metacarpo-phalangeal and interphalangeal joints of the third digit, 

 characters it possesses in common with most forms of the Embal!anurina\ The types 

 of upper molar, namelj', in the presence of a hypocone, is also met with in EmhuJla- 

 niirn. The last upper molar in both gronps exhibits a nearly perfect second V. The 

 large by]»oconid in the last lower molar is repeated in all the cmbalJanurines in- 

 cluding Fnrin. Ada])tation to active motion with wing at rest is seen in all. The 

 greatest degi-ec of the a(lai)tation last nanuMl is seen in Vhciromelcs oil^o\•n^io, though 

 the other genera of the group are rapid flyers. 



