MAMMALS OF NORTHERN COLOMBIA — HERSHKOVITZ 445 



Artibeus (Proc. Zool. Soc. London, 1908, pp. 224-319) the female of the 

 pair from El Salado is properly identified as A. jamaicensis, owing to 

 the absence of the rudimentary third upper molar. The male, taken 

 together with the female, has a third upper molar in each jaw and 

 should be referred to A. planirostris planirostris. However, both 

 specimens are so obviously alike otherwise that it would be folly to 

 persist in the illusion that the presence or absence of the evanescent 

 third upper molar is of more than individual or local significance. 

 Examination of the large series of Artibeus in the collections of the 

 United States National Museum and of the Chicago Natural History 

 Museum confirms the absolute unreliability of the dental formula 

 for separating A. jamaicensis from A. planirostris. The indications 

 are that the number of upper molars may be an individual as well 

 as a geographic variable. The incidence of M^ appears to be highest 

 in the Artibeus of Brazil, upper Amazonia, the Guianas, Trinidad, 

 and the Grenadines and lowest in Paraguay, the trans-Andean regions, 

 and in Central America and Mexico. Whatever Andersen may have 

 had in mind, the relationship between the form of the posterior border 

 of M^ and the presence or absence of M^ pointed out by him {op. cit., 

 p. 252) has no specific significance. The posterior border of the 

 second upper molar may be emarginate w-here no trace of M^ exists, 

 and it is not always emarginate in the presence of M^. The third 

 upper molar may occupy any position behind the second molar 

 whether or not the posterior border of the latter is notched. In some 

 series where no third upper molar appears, an alveolus in various 

 stages of obsolescence may be present. In conclusion, it appears that 

 the small form, A. planirostris Spix, cannot be treated as other than 

 a specific synonym of the similarly small A. jamaicensis Leach. 



Living side by side with A. jam.aicensis is a markedly larger species, 

 the largest of the genus. The specimens of this species taken in El 

 Salado and other nearby localities are listed and discussed below under 

 the heading Artibeus lituratus palmarum. If Andersen were again 

 followed, this large species would be identified as A. jamaicensis 

 palmarum, thus recording the unhappy situation of two "races" 

 of the same species occupying identical habitats. 



ARTIBEUS LITURATUS PALMARUM Allen and Chapman 



Artibeus palmarum Allen and Chapman, Bull. Amer. Mus. Nat. Hist., vol. 9, 

 p. 16, 1897. — Allen, ibid., vol. 13, p. 89, 1900 {Bonda, ; femurvillosum Bangs, 

 a synonym). — G. M. Allen, Bull. Mus. Comp. Zool., vol. 52, p. 42, 1908 

 (femurvillosum; synonym). 



Artibeus fern urvillosum Bangs, Proc. New England Zool. Club, vol. 1, p. 73, 1899 

 (La Concepci6n, type locality); vol. 1, p. 101, 1900. 



Artibeus jamaicensis -palmarum, Andersen, Proc. Zool. Soc. London, 1908, p. 278 

 (revision) . 



Type locality. — Trinidad. 



