260 DK. KNUD ANDEBSEN ON BATS. [Apr. 7, 



Range. — From S, Brazil, Paraguay, and Pei'u, to Central 

 Mexico (Jalisco), including the West Indies ; no indisputable 

 record from Guiana. 



Races. — Seven races of Artibeus jamaicensis are described below, 

 viz., A. j. parvipes, yucatanicus, jamaicensis, mid aiqttatorialis ; 

 these four, as being probably of Central American and West 

 Indian origin, may be conveniently called the " northern " races ; 

 further, A . j. littiratus, palmarum, and pi-ceceps ; these three, as 

 being probably of South American origin, may be called the 

 " southern " races. 



Remarks. — A. jamaicensis is at once distinguishable from all 

 other species of the genus by the combination of these two 

 characters : molars f, maxillary tooth-row 9"3-12'2 mm. ; the 

 first character excludes all species with the exception of A . glaucus 

 and loatsoni, which possess a small m^ ; the second chaiucter 

 excludes the two latter species, A . glaucus and watsoni being very 

 much smaller (maxillary tooth-roAv 6 "5-7 mm.) 



There is no reliable external character by which A . jamaicensis, 

 all races taken together, can be discriminated from A. planirostris 

 s. lat. ; the nose-leaves, ears, wing-structure, coloration, even the 

 dimensions, are practically identical ; to the larger races of 

 i. jamaicensis (Jituratus, palmarum?) coi-respond the large A . plani- 

 rostris fallax; to the small races oi A. j. jamaicensis (2)arvipes, 

 9/ucatanicus, jamaicensis) the small races of A . planirostris (plani- 

 rostris, trinitatis, &c.); ^.^amaicejiSis might properly be described 

 as an " ^. planirostris " which has permanently lost m'^. Dobson's 

 way of discriminating the two species extei-nally — the front 

 margin of the horseshoe freeing, planirostris, bound down to the 

 muzzle in '■'■A. per.spicillatus " (A. jamaicensis) — would in 66 p. ct. 

 of cases lead to wrong or doubtful identification. 



But the matter becomes rather different when considering each 

 i-ace of A. jamaicensis separately. Brazil is inhabited by the 

 large A.j. liiuratus, whereas the race of A . planirostris occurring 

 in the same region (A. p. p)lanirostris) is considerably smaller, so 

 that only in very rare instances is there any difficulty at all in dis- 

 criminating these two forms. Guiana is inhabited by the largest 

 race known of A . jilanirostris {A . p. fallax) ; A . jamaicensis is as yet 

 not recorded with certainty from Guiana, and perhaps it has not 

 spread to that country. In Venezuela much the same contrast 

 obtains as in Brazil, A.j. jxdmariojn being as a rule considerably 

 larger than A. p. planirostris. A. jamaice^isis has spread over the 

 whole of the West Indies (parvipes, jamaicensis,p7xeceps) ; A. plani- 

 rostris is totally absent from the West Indies proper, having 

 spread only over the Venezuelan coast islands as far as Grenada. 

 Only Central America and Mexico are inhabited by certain small 

 forms of A. jamaicensis {jamaicensis, yucatanicus) which ex- 

 ternally, as a rule, are so completely like the small race of 

 A. planirostris {planirostris) living in the same region, as not to 

 be distinguishable without an examination of the teeth. 



