TWO NEW LICE. 



261 



remarks about metamorphosis, amounting to little more than a 

 profession of ignorance. (See, however, note in square brackets 

 on p. 272.) 



It seems very probable that, in the future, a careful study and 

 description of the immature stages of both Anoplura and Mallo- 

 phaga will prove largely the vehicle in which to arrive at a 

 sound classification of these two orders. 



Several points of interest have emerged from a study of the 

 immature stages of Polyplax brachyrrhynchus and P. oxyrrhynchus. 



In Pediculus vestimenti Warburton describes three stages : — 



Stage I. on hatching. 



„ II. after the first moult. 

 ., III. after the second moult. 



Oudemans in Philopterus macrocephalus and Liotheum jlavescens 

 describes three stages. 



In Polyplax oxyrrhynchus the immature forms are readily 

 sorted out into three stages. In P. brachyrrhynchus only one 

 stage w T as present. Little evidence can be given as to the 

 number of moults. One would suggest two as in Pediculits, but 

 from a study of a very instinctive slide in which the larva in 



Text-figure 10. 



MA 



Polyplax sp. Egg. X 63'3. MA. Micropyle apparatus. 



Stage I. of P. oxyrrhynchus is about to moult, and the new instar 

 can be seen through the old skin, it seems evident that a larva 

 changes its skin at least once with very little or no change 

 in form or chaatotaxy. On the other hand, in the last ecdysis 

 the change from Stage III. to the imago is quite abrupt, as was 



