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PROCEEDINGS OF THE NATIONAL MUSEUM 



Figure 18.— Sympatiy of Plecotus mexicanus (triangular symbols) and Plecotus tozvnsendii 

 (circular symbols) in Mexico. 



Seasonal movement is not apparent in available samples (table 5). 

 P. mexicanus is found in northern and southern parts of its range in 

 both winter and summer. P. tomisendii has been taken at high eleva- 

 tions in the transverse volcanic belt (in the range of P. mexicanus) 

 in both summer and winter, has been found south of the belt in sprmg, 

 late summer, and fall, and north of the belt at all seasons. 



The theory of conspecificity becomes less tenable when seasonal 

 m.ovement of one or the other of the subspecies cannot be demon- 

 strated. The phenomenon of overlapping ends of a chain of sub- 



