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Joshua Laerm and James L. Boone 



1982); separating five Peromyscus species in New Mexico (Smart 1978); 

 and separating four Peromyscus species in Arkansas (McDaniel et al. 

 1983). These studies indicate that it is usually possible to distinguish 

 between morphologically similar species, but the characters necessary 

 to do so vary geographically. Thus, for example, the characters used to 

 distinguish between P. leucopus and P. maniculatus in New England 

 differ from those in Wisconsin or Kansas. This almost ad hoc approach 



Fig. 1. Southeastern distribution of the four Peromyscus species showing 

 collection location of the specimens used to build the model (•) and 

 specimens used to test the model (*). 



