176 THE ANIMAL. PARASITES OF MAN 



which contain encysted fasciolidce, were to blame, and he sup- 

 ported his views on a feeding experiment which seemingly 

 yielded positive results ; this, however, is not definitely proved. 

 Piana's statement that small land snails are the intermediaries has 

 also not been proved. 



LITERATURE. 



JORDENS, T. H. Entom. u. Helm. d. menschl. Korpers. Hof, 1802, p. 64. 



BREPA, V. L. Mem. fis.-med. sopra i princip. vermi di corpo. Rom., 1811. 



MEHLIS, C. F. L. Observ. Anat. de Dist. hep. et lane. Getting, 1825. 



DUBINI, A. Entozoograf. umana. Milano, 1850. 



PIANA, G. P. Le cercarie d. moll. stud, in rapp. colla pres. del D. epat. e I), lane. 



(La elinica vet^r., 1882, v.) 

 ASCHOFF, L. Ein Fall v. Dist. lane. i. d. menschl. Leber. (Areh.-f. path. An., 1892, 



cxxx., p. 493.) 

 ZSCHOKKE, F. Selt. Par. d. Mensch. (C. i. B. u. P., 1892, xii., p. 500.) 



Fam. 3. Schistosomidcz, Looss. 

 Gen. Schistosomum, Weinl, 1858. 



Syn. : Gyncscophorus, Dies, 1858 ; Bilharzia, Cobb., 1859 ; Thecosoma, 

 Moq. Tandon, 1860. 



Digenetic Trematodes, that are sexually distinct, and with the oral and 

 ventral suckers in close contiguity ; the females are filiform ; the males 

 have bodies that widen out considerably behind the ventral sucker, and 

 the lateral parts of which curl ventrally, forming the almost completely 

 closed canalis gynaecophorus, within which the female is enclosed. [The 

 female being longer than the male, part usually protrudes from the posterior 

 end of the male. F. V. T.] There is no pharynx ; the intestinal branches 

 reunite at the posterior end of the body. The genital orifices in both sexes 

 are in the middle behind the ventral sucker. There is no cirrus pouch. 

 The male has five or six testes ; the female one ovary ; the uterus is long. 

 There is no Laurer's canal. The ova are equally attenuated at either 

 extremity ; they have a small terminal spine, and are not provided with 

 a lid. They contain a miracidium, ciliated on all sides, which is characterised 

 by the possession of two large glandular cells, which discharge anteriorly 

 next to the gastric sac. They live in the vascular system of mammals. 

 (An analogous species [Bilharziella] lives in birds.) 



Schistosomum hcematobium, Bilharz., 1852. 

 Syn.: Distoma htzmatobium, Bilh. ; Dist, capense, Harley, 1864. 



The male is whitish, and measures 12 14 mm. in length, but is 

 already mature when 4 mm. long. The anterior end is 0*6 mm. or 

 a little over in length. The suckers are near each other, the oral 

 sucker is infundibular, and the dorsal lip is a little longer than 

 the ventral one. The ventral sucker is a little larger, 0^28 mm., 

 and is pedunculated. A little behind the ventral sucker the body 



