101 
THE RESPIRATORY SYSTEM OF MALLOPHAGA. 
By LAUNCELOT HAKRISON, B.Sc. 
Exhibition of 1851 Research Scholar of the University of Sydney. 
[From the Quick Laboratory, University of Cambridge.) 
(With 21 Text-figures.) 
CONTENTS. 
PAGE 
Introductory ......... 101 
Method of examination ....... 102 
Tracheal system of Myrsidea cucullaris .... 103 
General account—Introductory ...... 106 
The stigmata ...... 107 
The tracheae . . . . . .117 
Comparative notes and theoretical considerations . . . 120 
Taxonomic value . . . . . . . .123 
Conclusions . ........ 126 
References .......... 126 
Introductory. 
The respiratory system in Mallophaga has not hitherto been described 
in detail. Kellogg (1896, p. 45) gives the disposition of the main 
trunks in Tetrophthalmus, together with a figure; Snodgrass (1899, 
p. 170) adds nothing to Kellogg’s account; Fulmek (1907) dismisses 
the tracheal system with a paragraph; Shipley (1909) gives a detailed 
figure for Goniodes tetraonis which is neither complete nor altogether 
exact; and Mjoberg (1910), although devoting several pages of his 
morphological section to the respiratory system, is chiefly concerned 
with the occluding apparatus of the stigmata. He does, however, figure 
the main trunks in Eutrichophilus, and the occluding apparatus in 
Gyropus ovalis; and makes certain general statements which may be 
summarised as follows: 
There are two main tracheal trunks, united behind by a bow-shaped 
transverse branch. Prothoracic stigmata have only been demonstrated 
