TWO NEW LICE. 251 



Measurements of Polyplax brachyrrhynchus (in millimetres'). 



Length of antenna "16 



•16 



Polyplax oxyrrhynchus, sp. n. (Text-figs. 4-6, 8, 9, 11-13.) 



Proportion of the Sexes. <S <$ 243, $ $ 675, besides numerous 

 immature forms. Percentage of males ==26. 



External Form. Male. (Text-fig. 4.) — Head elongate ; pre- 

 antennal area long, conical ; postantennal bay small ; temple- 

 margins converge a little towards the thorax. On the ventral 

 surface is a raised diamond-shaped area with its long axis longi- 

 tudinal and running from the mouth to the thorax. Antenna : 

 First segment broad, squat, second longest. A large sensorium 

 at the postaxial distal angle of segment 4, extending across the 

 joint into segment 5. Thorax small, shorter than the head, with 

 convex lateral margins. Sternal plate as in figure 4 a. Legs: First 

 pair slender, third pair very powerful. Ooxse of first pair close 

 to each other, those of the second pair separated by a space, those 

 of the third pair large and .contiguous at their inner angles. 

 Abdomen very long (for measurements see p. 260). On seg- 

 ment 2 a small tergite, broader than long, with possibly a second 

 one weaklv chitinised and ill-defined. On each of segments 3, 4, 



