NO. 4 FLEA GENUS PEROMYSCOPSYLLA — JOHNSON AND TRAUB I9 



of the posterior margin of the seventh sternum, the sinus being much 

 wider, dorsal lobe much shorter and the lower lobe short and truncate ; 

 at times the margin may be almost straight (fig. 25), at times with a 

 broken margin. Both male and female, especially the male, have thin, 

 erect bristles on the mesonotum dorsally (fig. 22). 

 Length. — Male, 1.7-2.0 mm. ; female, 2.0-2.3 mm, 

 Holotype. — Female, from "Mus," Paradise, Ariz., Nov. 21, 1913. 

 Peromyscopsylla hesperomys adelpha probably ranges from north- 

 ern California south into Mexico and east into western Texas, Ne- 

 braska, Colorado, the Dakotas, and southern Alberta. Intergrades 

 between h. hesperomys and h. adelpha have been found in Wyoming, 

 North Dakota, and South Dakota (figs. 32, 33, 35, 36). It is interest- 

 ing to note that in one case a male and female taken from the same 

 animal showed characteristics of h. hesperomys and h. adelpha respec- 

 tively (figs. 33, 36). 



Records of Specimens Examined 



Canada. Alberta (Peromyscus sp.). 



Mexico. Michoacan (Peromyscus sp.). 



United States. Arizona : Apache County (Peromyscus boylii) ; Coconino 

 County (Microtus riifiniis) ; Yavapai County (Peromyscus truei). California: 

 Alameda County (Pcrogiiathus sp., Peromyscus sp.) ; Inyo County (Peromyscus 

 maniculatus) ; Lassen County (P. maniculatus) ; Monterey County (Peromyscus 

 sp., P. californicus, P. truei) ; Nevada County (P. maniculatus) ; Plumas 

 County (Microtus longicandus, Peromyscus boylii, P. maniculatus), Colorado: 

 Clear Creek County (Peromyscus maniculatus) ; Summit County (Peromyscus 

 sp.) ; Washington County, "chipmunk." Montana: Custer County (Peromyscus 

 maniculatus) ; Davidson County (P. maniculatus) ; Powder River County (P. 

 maniculatus) ; Rosebud County (Onychomys leucogaster, Peromyscus manicu- 

 latus). Nebraska: Dawes County (Peromyscus maniculatus); Sioux County 

 (P. maniculatus). Nevada: Douglas County (Peromyscus maniculatus); 

 Ormsby County (P. maniculatus) ; Nye County (P. maniculatus). New 

 Mexico : Bernalillo County (P. maniculatus) ; Colfax County (P. maniculatus) ; 

 Lincoln County (P. boylii, P. leucopus, P. truei) ; Rio Arriba County (P. 

 maniculatus, P. truei) ; San Juan County (P. maniculatus) ; Santa Fe County 

 (Peromyscus sp., P. truei, Dipodomys ordii) ; Taos County (Peromyscus ma- 

 niculatus) ; Valencia County (P. boylii). Texas: Terry County (Onychomys 

 leucogaster, Peromyscus sp.). Utah: Beaver County (Peromyscus sp.) ; Box 

 Elder County (Peromyscus sp.) ; Millard County (P. truei) ; San Juan County 

 (Onychomys leucogaster, Peromyscus maniculatus) ; Washington County (P. 

 maniculatus) . 



PEROMYSCOPSYLLA HESPEROMYS PACIFICA Holland, 1949 



Figures ii, 13, 16, 17, 24 



Peromyscopsylla hesperomys (Baker) Hubbard, Fleas of western North 

 America, p. 329, 1947 (part) (nee Baker, 1904). 



