40 



PROCEEDINGS OF THE NATIONAL MUSEUM 



vou 88 



originates near the median line a very little ways in front of the 

 forking of the excretory vessel, near the anterior ends of the testes 

 and the posterior border of the ovary. In serial sections it could be 

 traced to the shell gland. There is no seminal receptacle, but the 

 early folds of the uterus are filled with sperm mingled with ova. The 

 sperm-containing portion of the uterus extends anteriorly to the 

 posterior edge of the ventral sucker. Vitelline ducts lead to a small 

 yolk reservoir ventral to the shell gland. The ova are numerous and 

 measure about 0.04 by 0.02 mm. 



Table 12. — Measurements of eight specimens of Steringophorus furciger 



in 1}alsain 



Measurement 



Length 



Anterior end to ventral sucker. 

 Ventral sucker to posterior end 



Maximum breadth 



Oral sucker, length 



Oral sucker, breadth 



Pharynx, length 



Pharynx, breadth 



Ventral sucker, length 



Ventral sucker, breadth 



Mm. 



2.00 

 .53 



1.12 

 .77 

 .24 

 .28 

 .14 

 .14 

 .35 

 .42 



Measurements of No. 1 were made on a series of frontal sections. 

 It will be noted that No, 6 and No. 7 differ from the others in being 

 relatively shorter from the ventral sucker to the posterior end. 



Hosts. — Four-spotted flounder {Paralichthys oblongus) and com- 

 mon flatfish {Pseudopleuronectes americanu-s) . 



Record of collections. — ^^lany, collected June 1, 1907, from four- 

 spotted flounder. 



Many (U.S.N.M. No. 8188), collected June 1, 1907, from flatfish; 

 eight fishes examined. 



Mr. Edwards' notes state that many distomes were found in both 

 the four-spotted flounder and the flatfish. The vial of this date of 

 material from the four-spotted flounder contains but one distome, 

 while that with material from the flatfish contains 340 distomes 

 of this species. 



Genus LINTONIUM Stunkard and Nigrelli, 1930 



LINTONIUM VIBEX (Linton) 



Plate 20, Figures 268-271 



Distomum vihex Linton, Bull. U. S. Flsb Comm. for 1899, pp. 281, 291, 292, figs. 

 48-51, 1900; ibid. p. 464, 1901; BuU. U. S. Bur. Flsb., vol. 24, p. 402, fig. 

 188. 1905 (an error appears in the description and figure; the anterior 



