1915.] Allen, Review of the South American Sciuride. 301 
Rica, and an outlying form (Mesosciurus richardsoni) in Nicaragua. It 
occupies all of the Andean region south to Peru, and extends east in the 
Caribbean coast region to Trinidad. It comprises three quite distinct 
groups, as (1) the hoffmanni group, (2) the gerrardi group, and (3) the 
saltuensis group, no one of which overlaps the range of either of the others, 
pied 
Fig. 25. 1, Notosciurus; 2, Leptosciurus pucheranit group; 3, L. ignitis group; 4, 
L. leucogaster; 5, Guerlinguetus estuans-alphonsei group; 6, G. ingramt. 
so far as is now known. The hoffmanni group (subgenus M esosclurus) 
consists of a large number of forms (species and subspecies) all below 
medium size, and practically all of the same size, of the same general charac- 
ter of pelage, and of the same general style of coloration. The wide range 
