"GROUSE DISEASE "-STRONGYLOSIS 217 



fourth or fifth of its whole length. It is described as having a sheath ; but in the 

 specimens we have seen this was not apparent — probably it was retracted. 



The males are very much rarer than the females — in fact, we examined a consider- 

 able number of specimens without finding a single male : probably they occur in 

 about the proportion of one to seven or ten females. We have occasionally found a 

 very long, thin larva in the duodenum, which we take to be the larva of the Trichosome. 

 The eggs appear to undergo no segmentation in the body of the worm, and, in 

 fact, we have not yet seen an egg of Trichosoma longicolle segmenting. In one 

 Grouse from Ross-shire small embryos of some nematode were found in the small 

 intestine. It is possible that these are the young of T. longicolle, l)ut they show 

 no trace of division into neck and body. It is also possible that they are the larvte 

 of Trichostrongylus pergracilis ; but they differ in size and shape from those young 

 of this species which we have hatched out and found free. The Grouse in which 

 they were found have been feeding on corn, and I am rather inclined to believe 

 that these larvas are the young forms of Tylenchus tritici which causes the well- 

 known "corn-cockle." 



Trichosoma longicolle occurs only in the duodenum, often associated with the 

 species of Hyjnenolejns which inhabits this part of the alimentary canal. They are 

 surrounded by epithelial cells, singly and in clumps, and of many sizes and shapes, 

 which have been shed in immense numbers from the wall of the duodenum. These 

 may have been detached by post-mortem digestion. These worms have been found 

 in 13"6 per cent, of the birds examined ; but it must not be forgotten that they are 

 most inconspicuous and easily overlooked. They have been found in Grouse from 

 Montgomeryshire and Yorkshire, as far north as Ross-shire, and at all seasons. 

 They do not occur in large numbers, and their pathological effect seems small ; still 

 we must not forget that their near ally, the human parasite Trichocephalus 

 trichiurus {dispar), is one cause of peritonitis and appendicitis in man. 



However the nematode makes its way into the chick, it must, like the 

 Trichostrongylus, grow very rapidly. We have found specimens in a Grouse- 

 chick of fourteen days in age. 



(III.) Family Ascaridae. 



(iv.) Heterakis papulosa (Block). 



Stossich ^ mentions this round- worm, under the synonym of H. vesiculccris 

 Frohl, as occurring in the Grouse. It is a very common parasite in poultry and 



1 " Qlasnikhrvatskoga naravoslovnoga driiztva," Societas hidorico-naturalis Croatica, p. 284^ Zagreb, 1887. 



