9 
310 DR. A. E. SHIPLEY ON [ Mar. 16, 
larval stages in the body of some lower animal. This lower 
animal, presumably an insect or a molluse or a spider, must be 
eaten by a grouse and the larval tape-worm must be set free 
before the latter can grow up into the adult tape-worm which we 
find in the intestine of the grouse. In searching for this second 
host it was natural to begin with the ectoparasites, which one 
would imagine were continually being snapped up by the bird. 
We have, however, up till now completely failed to find any 
cestode-larve in the grouse-fly or in the numerous ‘“ biting-lice ” 
or “bird-lee” (Mallophaga) which abound on the skin and 
amongst the feathers of the grouse; and, what is still more 
significant and still more remarkable, we have, in the hundreds 
of crop-contents which we have examined, never found one of 
these insects in the grouse’s food. 
This report is based in the main on my own observations, but 
some of the facts recorded were first observed by Dr. E. A. Wilson, 
and some by Mr. J. C. F. Fryer, of Caius College, Cambridge. In 
fact, in looking back over the work | find it difficult to disentangle 
the precise share each of us had in it. One thing, however, is 
clear. I am indebted to Dr. Wilson for a very large proportion 
of the drawings which have been reproduced in the Plates at the 
end of this paper, and I am also indebted to him for lightening 
many pleasant hours spent, not on the open, breezy heather of 
the Scottish moors, but in the stuffy laboratory we were wont 
to improvise in the back premises of many a Scottish inn. 
To Mr. Edwin Wilson, of Cambridge, a word of thanks is also 
due for the accuracy and skill with which he has depicted the 
Grouse-fly and the Grouse-flea. 
ECTOPARASITES. 
INSECTA. 
A. MatropHaca.—Bird-lice or Biting-lice. 
Gi.) Fam. Philopteride. 
I.—G@oNIoDES TETRAONIS Denny. 
Tn his ‘ Monographia Anoplurorum Britannie,’ Denny * describes 
and figures this species, which he calls the “‘ Louse of the Black 
and Red Grouse.” He states that it is ‘‘common upon both the 
Black and Red Grouse” (Lagopus tetrix and L. scoticus). ‘‘ Upon 
the Willow or Hazel Grouse (Lagopus salicett) I find a similar but 
distinct species, rather broader in the abdomen, and of much 
darker colour.” Denny describes several species of the same 
genus which infest other game-birds. 
* Published by H. G. Bohn, London, 1842, p. 161, pl. xiii. fig. 3. 
