STUDIES OK THE ECTOPAKASITIC TBEMATODES OF JAPA^^ 2l3 



ceeds straight forwards towards the common genital opening. Pairetl 

 yolk-cliwts sUghtly asymmetrical, making an angle with the long 

 axis of the body, and uniting with each other on the same 

 level as the fore end of the ovary. The unpairel yolk-duct 

 thence proceeds backwards and towards the left, and unites with 

 the oviduct in the median line of the body, just where the oviduct 

 bends to the left towards the ootyp. Geiiito-iiitestinal ccuial tolerably 

 long, and arising from the oviduct side by side with the receptaculuin 

 seininis, proceeds slightly forwards and towards the right, and finally 

 opens into the intestine. Testes exceedingly numerous, tolerably 

 large, extending from a little behind the common genital opening to 

 the level of the first pair of posterior suckers, and occupying the 

 w^hole region enclosed by the two intestinal trunks, i. e., three- 

 fifths of the total breadth of the body. Vas deferens as usual on the 

 dorsal side of the uterus. 



Habitat — Mouth-cavity of Choerops Japonicus (Jap. Kobu-dai or 

 Kan-dai). Young specimens also on the gill. 



Locality — Mitsugahama (Prov. lyo). 



Date — August 1889. 



ti. Diclidopliora tetrodoiiis, n. sp. 

 (PI. X, figs. 1-4.) 

 Body long and slender, spathulate, 5-15 mm. long, divisible into 

 three portions, an anterior, fusiform portion a little over half the entire 

 length of the body, a middle, slender, stalk-like portion half as long 

 as the former, and the caudal disc a little less than h:ilf the stalk-like 

 portion and bearing the suckers along its margin on the ventral side ; 

 the three portions, however, gradually passing into each other with- 

 out any sharp demarcation. Suchers sessile, elliptical, arranged in a 

 deep horse-shoe shape, the open end of which is directed forwards ; 



