new Species of Lice. 95 



sac-like, witliovit any external signs of segmentation except 

 in the ($ . In tliis sex there is a pair of rather large pleurites 

 on the two basal segments ; on each of the others, up to 

 the seventh, a pair of small, narrow, chitinous slips situated 

 transversely in the pleural region on each side. In the ? 

 these slips are absent, but there are two pairs of large 

 pleurites at the base and one pair at the end, on the penulti- 

 mate segment of the abdomen. 



External Form. Male. — Head : fig. 2 is an accurate 

 representation of the outline of the head, and makes un- 

 necessary the usual circumlocutionary phrases. The notable 

 features are the rather deep semicircular frontal sinus (which 

 lias a deep marginal band of dark brown chitin divided into 

 two parts by a median longitudinal line), the large size of 

 the basal segment of the antenna, and a gular plate (see 

 fig. 3, GP) broader than long, lying between the two longi- 

 tudinal bands that rmi forward on the ventral surface of the 

 skull*. 



There are two sm.all circular sensoria close together on the 

 ventral surface of the third segment of the antenna. 



Thorax : the parts were too crushed to allow of description. 

 Apparently it resembles that of the ? closely. 



Abdomen : the first two pairs of pleurites are large plates 

 with a firm outer but an irregular ijiner margin, the second 

 pair a little smaller than the tirst, both of a deep brown 

 colour. On the succeeding segments the pleurites are small, 

 tliin, transverse slips. At the posterior end of the last 

 segment are two lobes forming the hind margin of the 

 segment and apparently tlie posterior lip of the genital 

 opening, 'i'hese two lobe-like pieces are rounded and white, 

 covered with short bristles ; they run in towards one 

 another, but do not meet. Two brown bands of chitin 

 run forward on the ventral surface as far as halfway to the 

 base of the abdomen, one on each side of the copulatory 

 aj)paratus, which is seen through the transparent integument. 



The above description is necessarily incomplete, and may 

 have to be emended in some respects when new and better- 

 preserved material is forthcoming. 



External Form. Female (fig. 3). — The usual sexual 

 diff'erences in the antennae (see figure). 



Thorax : pronotum is quite short ; lateral margins slightly 

 divergent the one from the other. Meso + metanotum equally 



* A gular plate of this character is present in many Mallophaga, 

 e. g., Nirmus varius, Nitzsch, Nirmus vidyatus, KelL, Lipeurus quadri- 

 pustulatus, Piag. The peculiar structures in this part of the head in 

 Ancisfrona and Pseudomenopon tridens are, perhaps, modi tied gular plates. 



