40 ILLINOIS BIOLOGICAL MONOGRAPHS [258 



bifurcation of the intestine the uterus reaches in a relatively straight 

 stretch to the genital atrium. 



The eggs are large, thick shelled ovals, measuring 161 /z in length by 99 /u 

 in breadth. The double, dark eyespots give evidence of the developing 

 miracidium within the eggs before they have passed in their course anterior 

 to the middle region of the body. 



Habitat: Abdominal air-sacs. Locality: host taken in Raleigh 



Host: Totanus melanoleucus (?) N. C. 



Date: April 7, 1894 Collector: W. C. Hall 



No. 21.90 Ward collection 



Habitat: Liver? or Lung? Locality: Creston, Iowa 



Host: Totanus soUtarius Collector: W. C. Hall 



Date: Aug. 30, 1895 No. 21 . 763 Ward collection 



Filed among the records of Hall is a statement that he collected 5 

 specimens from the air sacs of Totalnus flavipes Sept. 4, 1895, which he 

 believed to be this species. The material from this host has not been found. 

 This species is most closely related to Cyclocoelum brazilianum Stossich 

 and resembles that form in the lateral extent of the uterus, the relative 

 position of the genital glands, and in the size of the ovary. It differs, 

 however, in the size of the testes, the more weakly developed vitellaria, 

 and relative size of the oral sucker and pharynx, these being of equal size 

 in C. halli while in C. brazilianum the sucker is distinctly larger than the 

 pharynx. 



CYCLOCOELUM WILSONI nov. spec. 

 [Figure 6] 



Medium sized monostomes 12 mm long by 3 mm wide in maximum 

 which is found at the beginning of the posterior one-fifth of the body. 

 Posterior and bluntly rounded. Anterior to the point of greatest width 

 the body tapers gradually to a blunt but relatively small point. The 

 mouth sucker measures 374^i in diameter and is one-third larger than 

 the oval pharynx which measures 298/x in length by 269/1 in width. The 

 esophagus is relatively long and gives rise by bifurcation to the simple 

 intestinal crura, which as in other species run parallel to the body wall 

 and anastomose in the posterior end of the body. The genital aperture 

 is ventral to the middle of the pharynx. The cirrus pouch extends from 

 this point to the middle of the intestinal bifurcation. The follicular yolk 

 glands extend from the anterior wall of the intestinal bifurcation almost 

 to the excretory bladder at the posterior end. In lateral expanse they pass 

 over the external wall of the intestinal crura to the middle of that organ 

 where they meet the furthest expanse of the uterus. The uterus in this 

 species lies entirely anterior to the anterior testis and fills out the space 

 between the crura, folding both dorsally and ventrally over the walls of 



