16 



PROCEEDINGS OF THE NATIONAL MUSEUM 



Vol. 68 



A.* Scarcely half of the body setae arranged into definite transverse rows, those 

 that are not so arranged are spinelike or peglike ; number of setae in 

 ventral row on segment VI of female typically 12 (11 to 13) ; diameter 

 of spiracle bulb considerably over a tenth of a millimeter 



P. (Pediculus) huraanus humanus Linnaeus. 



PEDICULUS (PEDICULUS) HUMANUS NIGRITARUM Fabricius 



Plate 2, figs. 6 and 7 ; text figs. Ic, 2, 3c, 5, 6 



1805 Pediculus nigritarum Fabricius, Systema Antliatorum, p. 340. 

 1816 Pediculus nlgrescens Olfers, De vegetativis et animatis corporibus 

 in corporibus anincatis reperiundis commentarius. Pars I, p. 



81. Berlin (Reference from Fahrenholz, work not seen by 



writer ) . 



Fig. 6. — Ventral view of end of left anterior leg of male of pediculus (pediculus) 

 humanus nigritarum fabricius 



Female. — Head about as broad as loni^; forehead about twice as 

 broad as long, not swollen; eyes less conspicuous than in most 

 forms of Pediculus; postocular tubercle reduced. Antennae equal 

 to or slightly surpassing the head in length; segment I frequently 

 as long as or longer than broad ; segment II twice as long as broad 

 but not as long as III plus IV; segment III decidedly broadened 

 distally and about one and a half times as long as broad ; segment 

 IV scarcely at all broadened distally, slightl}'^ longer than broad and 

 shorter than III ; segment V about twice as long as its width at the 

 base and equal in length to segment II. Macrochaetae of thorax 



