D. Keilin and G. H. F. Nuttall 
281 
Text-fig. 1. Pediculus humanus race corporis <$. Normal internal sexual organs, showing their 
position in the abdomen as seen by transparency from the dorsal side. The basal plate, 
dilator and vasa deferentia are schematized, acc.gl. = accessory gland, d.ej. = ductus ejacula- 
torius, dil. = dilator, t. =testis, v.def. = vasa deferentia, v.sem. — vesicula seminalis. (K. & 
N. del.) 
Text-fig. 2. Pediculus humanus race capitis <$ (Lot 237, Nairobi, Brit. E. Africa). Normal, deeply 
pigmented specimen (A) in dorsal and (B) in ventral aspect, d.b. = dorsal bands, v.h. = ventral 
band, v.pl. = ventral plate; the last two structures vary in form as figured. (N. del. 
