716 Laura Florence 



mixture method introduced by Apdthy (1912:464, 468; also Kornhauser, 

 1916) was used, but it gave no better results than Gilson's rapid method 

 and involved many more steps. After double-imbedding it was found 

 possible to make good series of longitudinal and transverse sections of 

 5 microns, 7| microns, and 10 microns, in thickness. 



The reagents used for fixing were Zenl<er's fluid, Bouin's fluid, and 

 Flemming's weak solution. In every case the insect was chloroformed and 

 its legs were cut off close to the thorax before it was placed in the reagent. 

 Both the Zenlver-fixed and the Bouin-fixed material were stained with 

 hematoxylin and eosin, hematoxylin and orange G, and methjdene blue 

 and eosin. In addition the Bouin-fixed material was stained with Mallory's 

 anilin-blue connective-tissue stain, a combination used by Kingery (1916: 

 292) in studying the intestine of the grasshopper. This stain differentiates 

 the chitinized from the non-chitinized cuticula, the former staining red 

 and the latter a clear blue, and also Ijrings out strikingly the striations 

 of the muscle fibers. The Flemming-fixed material was stained with 

 iron hematoxylin according to the method of Heidenhain, and with 

 safranin, a solution made of equal volmnes of a water-soluble and an 

 alcohol-soluble stain being used. 



All measurements given in the text were made with an ocular micrometer 

 valued in terms of a stage micrometer used in a Zeiss microscope fitted 

 with an objective A, 15 milhmeters, and an ocular No. 2, and ha\ang a 

 tube length of 160 milhmeters. 



SUMMARY 



At the close of his paper on the mouth parts of the body louse, Harrison 

 (1916 b: 218) has pointed out the many resemblances found by himseh and 

 other workers lietween the Siphunculata (Anoplura) and the Mallophaga, 

 particularly those of tire suborder Ischnocera. The present study has 

 served to again emphasize the general similarity in structure of the two 

 groups, and has brought to light some structures which have not yet 

 been described in tliis order. 



No mention of the apoilemes extending from the dorsal to the ventral 

 surface of tire thorax has been foimd in the literature. While the name 

 suggested for them — the apodemes of the prothora.x and the prosternum 

 — is intended to call attention to their position in tlie anterior part of the 

 thorax, it must not be forgotten that they probably originated as invagi- 



