STUDIES ON THE ECTOPAEASITIC TEEMATODES OP JAPAN. J9§ 



in front, but apparently continuous behind. Testes occupying a 

 comparatively small ai'ea about one-sixth the whole length of the 

 body, posterior to the ovar^'; of moderate size and comparatively 

 few in number (about 15). No lateral branches on the median side 

 of the intestinal trunks; the left trunk longer than the right. Caudal 

 disc continuous with the rest of the body, and the suckers occupying 

 nearly one-half the whole lateral borders of the body; suckers 30-33 

 or more on each side; breadth 0.046-0.065 mm. 



Habitat — Gill of Centronotus nihilosus (Jap. Gimpo). 



Locality — Mitsugahama. 



Dfl^e— August 1889. 



7. Microcotyle cliiri, n. sp. 

 (PL n, figs. 4 & 5 ; PI. Ill, fig. 5 ; PI. V, fig. 4.) 

 Body about 4.2 mm. long, symmetrical, slender in the antei'ior 

 portion where the vitellarium is absent, but the remaining portion 

 much broader, rounded at both ends. Common genital opening 

 situated a little in front of the hinder end of the oesophagus; genital 

 atrium with a hemispherical, cup-shaped organ on the dorsal side, the 

 inner surface of which is covered with spines similar in shape to those 

 of 3![. reticulata, and about 0.015 mm. long. The front half of the 

 ovary follows in its course nearly the three sides of an isosceles triangle 

 whose apex is directed backwards ; and the posterior half is many 

 times folded on itself into a close, irregular spiral. Vaginal opening 

 single, median, and dorsal, nearly half as far behind the common 

 genital opening as it is before the front end of the ovary. The 

 vaginal canal divides into two at a point which is about half as far 

 from the vaginal opening as from the anterior end of the ovary, and 

 the two canals, after traversing only a short distance, become continu- 

 ous with the paired yolk-ducts. These unite a little in front of the 



