220 S. GOTO. 



canal at first single, but soon divides right and left into two canals, 

 which then proceed backwards on the inner side of the inner intestinal 

 trunks, and become continuous each with the paired j^olk-duct of the 

 same side. Testes tolerably numerous, of moderate size, situated 

 between the inner pair of intestinal trunks behind the ovary, and 

 extending to the constriction which divides the middle from the 

 posterior portion of the body. 



Habitat — Gill of Thynniis sibi (Jap. Shibi). 



Locality — Hagi and Osatsube (Hokkaido, where it was collected 

 by my friend , Mr. N o z a w a) . 



Date— August 1889 (Hagi). 



2. Hexacotyle yrossa, n. sp. 

 (PI. XIII, figs. 4-6 ; PI. XIV, 6-7.) 

 Body flattened, elongated, thick, about 18 mm. long, divisible 

 into three portions as in the preceding species, but the anterior slender 

 portion with lateral swellings at a short distance from its front end 

 and passing more gradually into the middle, broad portion, and with 

 the hindmost portion shorter than in H. acuta. The innermost 

 small pair of suchers situated in a line with the posterior borders of the 

 other suckers. Chitinous pieces of the suckers as represented in fig. 6, 

 PI. XIII. Inner pair of hooks very much smaller than the outer, solid, 

 with strongly recurved ends, bent at a right angle at the middle of its 

 whole length, 0.01: mm. long if the middle bending be straightened 

 out; outer pair entirely hollow, with a rather thin wall, with 

 strongly recurved, pointed end, and with a large process at the 

 middle of its length, 0.126 mm. long (curvature not reckoned); 

 their forms as represented in fig. 5, PI. XIII. Oesophagus and intestine 

 disposed as in H. acuta, the only difference worth noting being that 

 the inner pair of intestinal trunks converge at a short distance in 



