ANIMALS WHICH LIVE ON OR WITHIN GROUSE 197 



the moors have also been examined in the hope of throwing 

 some light upon the life history of the Grouse tapeworms. 

 The specimens l investigated were collected by Mr P. H. Grim- 

 shaw, of the Royal Scottish Museum, but here again the 

 investigation has not met with success. 



We may now proceed to describe the tapeworms of Grouse. 



Fam. TAENIID^E. 



XI. Davainea urogalli (Modeer, 1790.) 

 (The "Large" Tapeworm of the Grouse.) 



Of the three tapeworms which are found in Grouse, this species, 

 originally described from Lagopus scoticus in 1853, by Baird is the 

 commonest and by far the largest. It occurs in many allied forms, 

 e.g., the blackcock, the capercailzie, and according to Krabbe in a 

 partridge, and one of the Himalayan pheasants. It appears at an 

 early age in the young Grouse : a specimen, 35 cms. in length, has been 

 taken from the intestine of a bird about three weeks old. Curiously 

 enough, it was an abnormal specimen, the worm having split ; and 



1 In the manner indicated, the following insects were examined in every case by 

 looking through the debris of some four or five specimens. 



DlPTERA. 



(i. ) Monophilus ater, one of the sub-family Limnobiin* of the Tipulidse. 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. This also proved a blank. 



(iii.) Cyrtoma spuria, one of the Empidse. This fly is small and seemed to have 

 little interior ; no trace of a cyst was found. In another small Empid fly a Gregarine 

 was discovered. 



(iv.) Scatophaga sp. Scatophaga stercoraria is perhaps the commonest fly in 

 Scotland, and, owing to its larvae living in the droppings of the Grouse, it can hardly 

 fail to contain the eggs of the cestodes ; but no Scatophaga has ever been found in the 

 crop of a Grouse, and there is some reason to doubt if the tapeworm eggs develop in 

 this fly. After searching for a long time through the tissues of many specimens of 

 Scatophaga, only one ovum was found, apparently of Davainea urogalli, and that was 

 no further advanced than when it was laid. 



PLKCOPTEEA. 



Similar gropings through the disjected membranes of an unknown species of Perlid 

 produced no better results. 



ARACHNIDA. 



The tissues of a spider very common on the moors, and of a phalangid were also 

 investigated with a similar want of success. 



