226 The Ruffed Grouse 



Helminths, which are internal, parasitic worms, divided into three 

 classes, the roundworms (Nematodes), tapeworms (Cestodes), and 

 the flukes ( Trematodes ) . 



Protozoa, microscopic, single-celled animals. 



Bacteria, viruses, and fungi. 



Ectoparasites, including flies, lice, ticks, fleas, and mites. 



The Nematode Worms (roundworms). At least fourteen species of 

 roundworms have been found in the ruffed grouse, of which nine 

 are known to occur in the eastern seaboard states. In the listing be- 

 low, those of most significance are placed first. 



Dispharynx spiralis (Molin, 1858) Skrjabin 1916 b. This stomach 

 worm (see Plate 35) attacks the biid's proventriculus or glandular 

 stomach, but is also occasionally found in the gullet and the intes- 

 tine. It affects a number of hosts in addition to the grouse, includ- 

 ing the domestic chicken, dove, robin, turkey, and guinea fowl. 



It is a small, whitish worm a little less than half an inch long, 

 which attaches itself by its head to the mucosa of the stomach, and 

 usually rolls its body in a spiral.^ There is usually a swelling of the 

 organ, the degree depending upon the severity of the infection. 

 There is a small, bloody lesion of the epithelial tissue, which spreads 

 to redden the entire mucous surface ff many worms are present. In 

 such cases the lumen ( passage ) is reduced by swelling of the walls. 

 In the most serious cases, the worms penetrate and destroy the gas- 

 tric glands. This is accompanied by an excessive secretion of a white, 

 glary mucus. In some cases the proventriculus is perforated, result- 

 ing in a fatal peritonitis. 



In severe infections, the digestion is severely impaired and emacia- 

 tion results. Death commonly results from the primary tissue de- 

 struction and starvation. Most of the infections are produced by a 

 few worms. AUen and Gross (1926) found the usual infection to be 

 "from three or four up to a dozen." However, they recorded one case 

 of two hundred and twenty-eight parasites. Evidence indicates that 

 infections with twenty to thirty worms are suflBcient to affect the 

 bird's health and those more severe may prove fatal. 



The Iffe history of the parasite begins with the eggs passing out 

 of the grouse in its droppings. These are eaten by sowbugs (Porcellio 

 laevis) which are the intermediate hosts. Here the embryos escape 



1 See Cram ( 1927) for full description. 



