D. Keilin and Gr. H. F. Nuttall 305 
fragment, whilst the left part is fused with the $ plate to form its lateral 
extension. Gonopods normal. Posterior abdominal lobes reduced. 
No. 119 (Text-fig. 20) resembles the foregoing but is of special interest. 
Dorsal bands invisible. Legs: pair I as in <$, pair III as in $. $ genitalia in 
Text-fig. 20. Pediculus humanus, cross between capitis and corporis. Specimen 119, of inter¬ 
mediate type between $ and £. Posterior half of abdomen, ventral aspect, external 
and internal structure seen by transparency. Midgut {mg.), ova ( ov .), accessory gland of $ 
( acc.gl.Q ), gonopods ( gon .), posterior abdominal lobes of $ (p-l-), vesicula seminalis (v.sem.), 
accessory gland of $ ( acc.gl.tf ), penis (pen.). (K. del.) 
the form of an extruded sack, reduced in size, but bearing a strongly chitinized 
penis; dilator apparently obsolete. Posterior lobes as in $. Gonopods normal. 
$ ventral plate slightly irregular. $ ventral plate in two distinct pieces of 
irregular form, situate near the $ ventral plate. Dorsal abdominal muscles 
20—2 
