AET. 18 THE TREMATODE FAMILY SCHISTOSOMIDAE PRICE 7 



gynaecophoric canal. Seminal vesicle small, in front of testes. 

 Genital pore opens in median line about the level of the first testis. 



Female 15 mm. long, filiform, and about 170|a wide. Suckers small ; 

 acetabulum situated about 224/x to 252/a caudad of the oral sucker. 

 Digestive system similar to that of male. Ovary elongate, in anterior 

 half of body and immediately in front of cecal union. Uterus short 

 and usually containing but one Q,gg at a time. The vitellaria occupy 

 about two-thirds of body length, extending posteriorly from imme- 

 diately caudad of cecal union. Egg oval, 120;ii to 160/j. long by 

 60ja to TO/x wide, and provided with a strong lateral spine. 



Cercwria furcocercous, apharyngeal, spinose. Body 140|a to 190/i, 

 long" by 50/i to 75/x wide ; tail stem 200;a to 260/x long by 25/x, to 40/x 

 wide; furcal rami oO/a to 75/^ long. Oral sucker 30/a to 60/^ wide; 

 acetabulum small. Penetration glands consist of two pairs of large 

 nucleated acidophilic, granular cells and four pairs with small nuclei 

 and basophilic cytoplasm; penetration gland ducts very thick, open- 

 ing at the anterior end of oral sucker and capped by six pairs of 

 hollow piercing spines. Germ cells small and situated caudad of 

 acetabulum. Excretory system pattern consists of three pairs of 

 flame cells in the body and one pair in the tail stem. 



Hosts. — Primary, man, and experimentally, rats and mice ; second- 

 ary, snails {Planorhis boissyi in Egypt; Plwiorhis j)feife?''i, Phy sop- 

 sis africaruz and Bidinus tropicus in South Africa; Planorhis guade- 

 lup&nsis in Venezuela; Planorhis centimetralis and P. olivaeeivs in 

 Brazil; and P. antiguensis in the West Indies). 



Location. — Mesenteric veins. 



Distribution. — Africa, South America, and West Indies. 



SCHISTOSOMA JAPONICUM Katsurada, 1904 



Figs. 12-16 



Synonyms. — Schistos&ma cattoi K. Blanchard in Catto, 1905, p. 

 70-73; BUhnrzia japonica (Katsurada, 1904) Hutyra and Marek, 

 1913, p. 1128. 



Specific diagnosis. — Schistosoma : 



Male 9.5 to 17.8 mm. long by 557/a to 967/x wide. Cuticle smooth ex- 

 cept for small spines along gynaecophoric canal and in suckers. Oral 

 sucker subterminal, 200)U, to 350/i, in diameter; acetabulum peduncu- 

 lated, 156/j, to 420/A in diameter, situated 550)u, to 780/x caudad of oral 

 sucker. The digestive tract is similar to that of S. haematohium; 

 intestinal ceca unite caudally about one-fourth of body length from 

 posterior extremity of body. Testes 7 in number (6 to 8 according 

 to some authors), situated near anterior end of gynaecophoric canal. 

 Seminal vesicle spherical, 125/i in diameter, and situated immediately 

 in front of the first testis. 



