TREMATODES FROM EISHES — LINTON 147 



Smooth; genital pore at posterior edge of oral sucker; copulatory 

 organ short, ejaculatory duct not much convoluted; prostate large; 

 convoluted seminal vesicle at anterior dorsal border of ventral sucker ; 

 first testis usually near ventral sucker; vitellaria extend from oral 

 sucker to ovary ; ova about 0.024 by 0.018 mm. 



Measurements, balsam, lateral view : Length, 13.00 mm. ; maximum 

 breadth, 1.54 mm. ; oral sucker, length, 0,61 mm., breadth, 0.56 mm. ; 

 ventral sucker, length, 1.33 mm., breadth, 1,30 mm.; anterior end to 

 posterior border of ventral sucker, 3.24 mm.; anterior end to first 

 testis, 3.15 mm. ; second testis to ovary, 0.21 mm. ; ovary to posterior 

 end, 6.30 mm. 



Measurements made on a series of sagittal sections : Length, 10.00 

 mm.; maximum breadth, 1.26 mm.; oral sucker, length, 0.50 mm,, 

 breadth, 0.50 mm. ; pharynx, length, 0.30 mm., breadth, anterior, 0.08 

 mm., breadth, posterior, 0.15 mm. ; ventral sucker, length, 1.20 mm., 

 breadth, 1 mm. ; anterior end to posterior border of ventral sucker, 

 3.85 mm. ; anterior end to first testis 3.85 mm. ; second testis to ovary, 

 0.40 mm.; ovary to posterior end, 4.12 mm.; copulatory organ, re- 

 tracted, length, 0.24 mm., breadth, 0.07 mm. 



Host. — Ocean sunfish {Mola mola) . 



Record of collections.— Eleven (U.S.N,M. No, 8381), collected July 

 20, 1914, from intestine of host ; fusiform, elongate posteriorly ; trans- 

 lucent; intestine dark brown; uterus gi-eenish yellow. A number of 

 these distomes were clinging to cestodes {Ancystrocephalus micro- 

 ce'phalus) ; maximum length, compressed under cover-glass, about 

 18 mm. 



Fourteen (U.S.N.M. No. 8382), collected September 3, 1925, from 

 intestine of host ; 20 mm. in length, in alcohol. 



Genus ACCACLADIUM Odhner, 1928 



ACCACLADIUM SERPENTULUS Odhner 



Distomum nigroflavum Rudolphi, Linton, Proc. U. S. Nat. Mus., vol. 20, pp. 530, 

 531, pi 48, figs. &-11, pi. 49, figs. 1, 2, 1898 ; Bull. U. S. Fish Coram, for 1899, 

 p. 282, 1900 ; iUd., p. 406, 1901.— Sumneb, Osburn, and Cole, BuU. U. S. Bur. 

 Fisheries, p. 31 ; pt. 2, p. 583, 1911. 



Accacladium seipentulus Ouhneb, Zool. Anz., vol. 77, pp. 173-174, fig. 3, 1928. 



Nearly smooth, but with a few minute, scattering papillae at the 

 anterior end. There is a blunt papilla in the oral sucker at the 

 entrance of the prepharynx. Genital pore some distance back of 

 posterior edge of oral sucker. In a series of sagittal sections, distance 

 between oral and ventral suckers about 2 mm.; the genital pore is 

 about 0.5 mm. back of the oral sucker. Copulatory organ rather 

 large ; in a series of sagittal sections, length, 0.70 mm., diameter, 0.14 

 mm., tapering to 0.07 mm. at its anterior end. The prostate is well 



