An Account of the Bird-lice of the Genus Docophorus. 171 
p XXII.—An Account of the Bird-lice of the Genus Docophorus 
(Mallophaga) found on British Auks (continued). By James 
Waterston, B.D., B.Sc., Imperial Bureau of Entomology. 
<a 
(MS. received 15th September 1914. Read 26th October gs 
JUN & 
(B) MorpHoLogicAL—THE MALE cat 
and exact Bentic characters is becoming ioe evident. So very ae 
defined indeed are the chitinized portions of these organs, that it is in many 
cases possible by this means to determine accurately mere fragments of insects 
so bleached and rubbed as to be otherwise unrecognisable. Before describing 
in detail the species of Auk Docophori, already referred to, I think it useful 
to figure and annotate the external ¢ sexual apparatus of each, and to 
indicate shortly, by a table, how the five forms may thus be separated 
without recourse to any other characters. 
The descriptive terms now employed have in part been recently 
i introduced, and all are explained in Ann. South Afy. Mus., vol. x., pt. 1x., 
No. 14, pp. 279, 280, July (1914). The following short account will make 
subsequent description more intelligible :— 
The copulatory apparatus (g) in Docophorus, Nirmus, ete., consists of an 
internal chitinized lamina—the basal plate—to which many strong muscles 
are attached. JDistally this plate bears a pair of laterally placed, freely 
movable blades (paramera), within which are two basally articulating and 
practically fixed more leaflike sclerites (endomera), from which issue apically 
a much smaller pair of telomera. Together the parts within the paramera 
may be referred to as the mesosome. The true penis is a simple chitinized 
tube lying immediately below, and often greatly exceeding in length, the 
‘telomera. The path of the penis inside the mesosome is as a rule easy to 
discern, especially apically. The hypomeron is the inferior support of the 
pems. When distinct it takes the form of a triangular, apically reflexed, 
hardly thickened membrane. . Oftener it appears as the expanded base of 
the penis. These terms are purely descriptive, at present. The exact 
nature of the parts to which they apply has still to be ascertained. 
The genitalia of Docophorus acutipectus show the typical parts clearly, 
and in Fig. 1 they have been separately labelled. No difficulty should be 
experienced in homologising the parts in the other species. 
VOL, XIX, M 
