1909. ] TAPE-WORMS OF THE RED GROUSE. 361 
of the insects and spiders which we examined are little, if at all, 
known, and more than once we have at first sight taken some 
organ proper to the insect for a cestode cyst, only to our great 
disappointment to discover later that we were looking at an ovum 
or other structure belonging to the putative host. 
During some days Dr. Wilson and I spent in Edinburgh towards 
the end of July, 1908, we examined a considerable number of the 
commoner insects found on the moors in the hope of throwing 
some light upon the life-history of the tape-worms so common in 
the grouse. The specimens we investigated were collected by 
Mr, P. H. Grimshaw, who is preparing a Report on the Insects of 
the Moors. We are greatly indebted to him and to the Keeper 
of the Museum, Mr. W. Eagle Clarke, and to Mr. J. Ritchie for 
kindly placing at our disposal a work-room and other accommoda- 
tion which greatly facilitated our work. When the insect had not 
been specifically named we always kept a similar specimen for 
subsequent identification in case it should contain the cyst; but, 
alas ! here again our jabour was in vain. 
In the manner indicated we examined the following Insects, in 
every case looking through the débris of some four or five 
specimens. 
DIprera. 
(i.) Monophilus ater, one of the subfamily Limnobiinz of the 
Tipulide. A very common constituent of the food of young 
grouse. No trace of a cyst was found, but in one specimen an 
immature nematode was wriggling about. 
(ii.) Bibio sp. Here again we drew a blank. 
(iii.) Cyrtoma spuria, one of the Empidee. This fly is small and 
seemed to have little interior ; no trace of a cyst was found. In 
another small Empid fly we discovered a Gregarine. 
(iv.) Scatophaga sp. Scatophaga stercoraria is perhaps the 
commonest fly in Scotland, and, owing to the larva living in the 
droppings of the grouse, it can hardly fail to contain the egys of 
the cestodes ; but we have never found a Scatophaga in the crop 
of a grouse, and there is some reason to doubt if the tape-worm 
eggs develop in this fly. After searching for a long time 
through the tissues of many specimens of Scatophaga, we only 
managed to find one ovum, apparently of Davainea wrogalli, and 
that was no further advanced than when it was laid. 
PLECOPTERA. 
Similar gropings through the disjected membranes of an un- 
known species of Perlid produced no better results. 
ARACHNIDA, 
We also investigated the tissues of a spider very common on 
the moors, and of a phalangid, with an equal want of success. 
Proc. Zoou. Soc.—1909, No. XXIV. 24 
