PROCEEDINGS OF THE 



ENTOMOLOGICAL SOCIETY OF WASHINGTON 



VOL. 23 FEBRUARY 1921 No. 2 



REMARKS ON THE GENUS HYSTRICHOPSYLLA TASCH. WITH 

 DESCRIPTION OF A NEW SPECIES. (SIPHONOPTERA.) 



Bv EDWARD A. CHAPIN, Washington, D. C. 



Through the kindness of Dr. Gordon F. Ferris, of Stanford 

 University, I have received three specimens of a flea of the 

 genus Hystrichopsylla Tasch. which appears to be undescribed. 

 I describe it herewith as 



Hystrichopsylla mammoth, n. sp. 



cf Head. The frontal notch is shallow and is quite low down on the anterior 

 margin of the head. On the front part of the head there are many bristles. 

 Of these bristles, seven are placed in a row from the base of the antenna forward 

 to a point a little below the frontal notch. There are two strong bristles on the 

 anterior edge of the antennal groove above the eye spot and one at the base of 

 the maxillary palpus and there is one more at about the center of the space 

 included by the bristles. In addition to these, there are many smaller hairs on 

 the lower half of the frons. The eye is not pigmented but is indicated merely 

 by a thickening of the chitin. The genal ctenidium is of six stout spines and 

 occupies about the anterior halt of the genal margin. The posterior angle of 

 the gena is heavily chitinized and somewhat prolonged. The occiput bears two 

 rows of bristles, the first (anterior) row of three and the second of five (with 

 several much smaller bristles in the line). The marginal row of spines contains 

 about thirteen on either side of the median line. The rostrum reaches almost 

 to the apex of the fore coxa. 



Thorax. The pronotum bears on its posterior margin a ctenidium of about 

 thirty-six spines or pairs of spines. That is, commencing with the fourteenth 

 spine from either side, the dorsal spines are very irregular but appear to be 

 grouped in pairs, one superimposed upon the other. The hairs on the meso anil 

 metathoraces are numerous. On the mesothorax, no order of arrangement is 

 maintained but on the metathorax the hairs are in five rows. The metepimeron 

 bears a vertical row of five large hairs directly below the metathoracic spiracle. 

 There are many other and smaller hairs on the sclerite. On the mesosternum 

 there is one very large hair. 



Abdomen. The tergites are thickly set with spinous hairs, the more posterior 

 of which are in rows. On the second, third and fourth tergites, along the 

 posterior margin there are rows of very short conical teeth, the numbers being 

 in order 7, 2, 2. The anrepynidial bristles are three on each side. Sternites 

 III to VII are thickly set, toward their posterior borders with many hairs. 



Legs. The spines and hairs which adorn the legs of this species are similar 



