NO. 4 FLEA GENUS PEROMYSCOPSYLLA — JOHNSON AND TRAUB 9 



Peromyscopsylla spinifrons, Jellison and Good, U. S. Publ. Health Serv., Nat. 



Inst. Health Bull. 178, p. 123, 1942. 

 Peromyscopsylla hesperomys Hubbard, Fleas of western North America, p. 329, 



1947 (part, not the records or drawings). 

 Peromyscopsylla hesperomys hesperomys Holland, Canada Dept. Agr. Techn. 



Bull. No. 70, pp. 176, 177, figs. 322, 324, /, 1949. 



Head (fig. i). — Preantennal area with three spiniforms at antero- 

 dorsal angle denoting frontal tubercle ; below these five to seven 

 medium-sized marginal bristles ; two dorsomarginal bristles between 

 spiniforms and upper margin of antennal groove; other than mar- 

 ginals, five long bristles arranged 1-2-2, and several small scattered 

 bristles. Genal process (G.P.) visible above genal ctenidium ; lower 

 genal spine the longer; genal lobe {G.L.) more than one-half length 

 of lower genal spine. (One female from Tennessee with three genal 

 spines on one side (fig. 37), cf. selenis description.) Second segment 

 of antenna with row of apical bristles on lateral surface not reaching 

 beyond second segment of club in male, usually about three- fourths 

 length of club in female, may reach apex. Postantennal area with four 

 or five irregular rows of bristles. 



Thorax (fig. 4). — Pronotum with row of five or six long bristles on 

 a side. Pronotal ctenidium with a total of 25-30 spines. Mesonotum 

 (MSN.) with five or six rows of bristles, first five of which are ir- 

 regular and of short bristles ; dorsally with short, heavy, erect bristles 

 from base to subapical row of long bristles. Mesepisternum (MPS.) 

 with three or four bristles; mesepimere (MPM.) with three rows of 

 bristles arranged 4-2-2 plus one bristle at posterior angle. Lateral 

 metanotal area (L.M.) with two bristles, dorsal longest (variable in 

 female). Metanotum (MTN.) with three rows of bristles. Metepi- 

 sternum (MTS.) with one long bristle; metepimere (MTM.) with 

 three rows of bristles but last row represented usually by a single long 

 bristle. 



Abdomen. — Typical terga with two rows of bristles, anterior of 

 which may be very short or absent on more posterior segments; 

 posterior row longer, reaching about to level of spiracles in male, 

 well below this point in female. Basal abdominal sternum with two 

 close-set bristles on ventral margin ; typical sterna with row of three 

 bristles in male, four to five in female. Male with three antepygidial 

 bristles, middle longest; female with three or four, usually four. 



Male (fig. 7). — Eighth tergum (ST.) with two rows of bristles 

 below and posterior to spiracle, the first of two medium-sized bristles, 

 second of about three much longer bristles. Eighth sternum (8S. and 

 fig. 15) with rather sharply rounded upper lobe bearing two or three 

 long bristles and one or two very small bristles apically; shallow 



