SQLTIRRELS OF MEXICO AND CENTRAL AMERICA 25 



and Microsciiinis are South American groups with numerous 

 species, and occur as intrusive elements in Central America, 

 where each is represented by one or two species. Otoscmrus 

 and Hesferosciiirus have few species and beloncr to the western 

 United States, but cross the border into Mexico. 



The first name available for a subgenus of American Squirrels 

 is Guerlingiietus Gray, 1821, of which Macroxiis'is a synonym. 

 3facroxus, the name which has been commonly used, has been 

 curiously diverted from its original application to include nearly 

 all American squirrels. Lesson was the first to misuse the name, 

 after which Gray went to even greater extremes, in which he was, 

 to a certain extent, followed by Trouessart in 1897. In 1880 the 

 last named author established several subgenera of American 

 squirrels, several of which were accepted by Merriam and 

 Allen; yet in 1897 he again lumped several of them in the 

 ancient confusion under Macroxiis. The most recently described 

 subgenus is Microsciurus Allen, 1895. 



LIST OF SUBGENERA WITH TYPE SPECIES. 



Echinoschirus^ type 6". hypopyrrhus Wagler (p. 25, 38). 

 Hesperosciuriis^ type S. griseus Ord (p. 27, S3). 

 Neosciurus^ ty-^e. S. carolinensis Gmelin (p. 27). 

 Otosciurus^ typs '^' ^<5(?;-/^* Woodhouse (p. 28, 85). 

 Tamiasciurus^ typs '^- hudsonicus Erxleben (p. 28, 87). 

 Arceosciurus, type S. oculatus Peters (p. 29, 88). 

 Parascinrzis^ typ^ '^- f^igcr Linnaeus (p. 30, 97). 

 Guerlmguetiis^ type S. guerlingiietus Gray (p. 30, 98). 

 Baiosciurus, type S. deppei 'P<t\.tr& (p. 31, loi). 

 Microsciurus^ type S. alfar i AWen (p. 32, 105). 



Subgenus ECHINOSCIURUS Trouessart (p1. I, fig. 9). 



JEchinosciurus Trouessart, Le Naturaliste, II, No. 37, Oct. 18S0, p. 



292; Cat. Mamm., Rodentia, pp. 80-81, 18S0 (part). 

 J/acroxz/^ Trouessart, Catalogus Mammalium, nov. ed., II, pp. 421- 



429, 1S97 (part). 

 Type Scitirus hypopyrrhus Wagler, from Mexico. 



^ Neosciunts is included here in order to complete the revision of the sub- 

 genera of North American squirrels. 



