194 S. GOTO. 



anterior end of the ootyp, and the single yolk-duct thus formed opens into 

 the oviduct ahout midway between the beginning of the ootyp and the 

 opening of the genito-intestinal canal. The latter opens into the oviduct 

 at the beginning of the last third of the whole course of the ovi- 

 duct. The vitellaria of the two sides are quite distinct in front as well as 

 behind, though the lobes of the opposite sides come close to each other. 

 Testes occupying a narrow region between the two trunks of the intes- 

 tine, posterior to the ovary; rather small in size; about 25 in number. 

 No lateral branches on the median side of the intestine; the two intes- 

 tinal trunks of equal length, and nearly reaching the posterior end of 

 the body. Caudal disc continuous with the rest of the body ; suckers 

 occupying the posterior half of the lateral border of the body; about 

 30 on each side ; brefidth 0.0&G-0.140 mm. 



Habitat — Gill of Chirus liexagramimis (Jap. Ainame). 



Locality — Hakodate. 



Date— August 1890. 



8. Microcotyle sciaenae, n. sp. 



(PI. II, figs. 6 & 6 a ; PI. VI, fig. 2.) 

 Body about 4 mm. long, slender, asymmetrical, rounded at 

 the anterior end and pointed posteriorly. Anterior sucker with a 

 septum. Common genital opening on the same level as the beginning ■ 

 of the intestinal trunks ; genital atrium armed with two sets of chitin- 

 ous rods arranged in circles (PI. VI, fig. 2, a & h). The longer 

 ones (a) are about 0.11 mm. long, each presenting two curvatures in 

 opposite directions, and are situated just in front of the opening 

 of the vas deferens. Only a small, terminal portion of these rods 

 projects into the cavity of the atrium, the remainiijg portion lying im- 

 bedded in the mesenchyma. The other shorter ones (b) have the 

 form of a hook and are about 0.02 mm. in length. These are arrang- 



