Family Hystrichopsyllidae Tiraboschi 85 



Female. Anterior margin of the head with a row of ten or 

 eleven bristles, of which two to four are short, toothlike spini- 

 forms, while the rest are of the usual form. Lower gena with 

 three long bristles, above which are three well-developed 

 bristles in series, more or less forming a diagonal across the 

 upper portion of the head. Frons and gena further armed with 

 numerous small setae. Upper of the two ctenidial spines much 

 shorter than the lower and closely associated with the long 

 spatulate genal process which extends well beyond it. Post- 

 antennal region of the head armed with four irregular rows of 

 bristles; first row consisting of about five bristles, second, third, 

 and fourth rows of six each. Between the second and third rows 

 are two or three irregularly arranged bristles. Along the poste- 

 rior margin of the antennal groove are a number of small setae 

 (Plate XXIII, fig. 117) . Pronotum with a single distinct row of 

 bristles and a ctenidium of fourteen or fifteen spines on a side. 

 Meso- and metanotum each with three or four irregular rows 

 of bristles. Each abdominal tergite with two rows of bristles. 

 First five abdominal tergites and the metanotum armed with 

 two or three stout dorsal teeth on a side. Sternite VII divided 

 by a deep sinus, the upper lobe prominent, more or less tri- 

 angular, the lower lobe wider. Tail of the receptaculum seminis 

 about three-fifths as long as the head, which is oval and gradu- 

 ally merges into the tail. For further details concerning the 

 structure of the female genitalia, see Plate XXIII, fig. 118. 



Male. Chaetotaxy of the head in the specimens examined 

 differing somewhat from that of the female. Anterior border of 

 the head armed with eight or nine bristles, of which the first 

 three in the vicinity of the fronto-genal angle are heavily pig- 

 mented and spiniform. Five long bristles situated in the upper 

 region of the head while the lower region bears three long, stout 

 bristles. Numerous small setae irregularly scattered over the 

 preantennal region of the head. Lower of the two genal spines 

 extending slightly more distad than the upper. Genal process 

 sometimes spatulate and sometimes rather slender, extending 

 well beyond the rounded termination of the upper genal spine. 

 Postantennal region of the head with about five irregular rows 

 of bristles; first row consisting of two bristles, second of three, 

 third of four, fourth of five, and the fifth or marginal row of 

 about seven. A series of about eight setae along the posterior 

 margin of the antennal groove. Modified segments: Genitalia 

 closely resembling those of P. catatina (Jordan) ; the movable 

 finger differing in shape, being widest below the middle and 



