STUDIES oys THE ECTOPAEASITIC TREMATODES OF JAPAN. 227 



teriorend, at the apex of which is attached a large, cir- 

 cular, saucer-shaped sucker, the cavity of which is 

 divided by means of elevated, radial spokes into a central 

 heptagonal area and seven quadrangular, peripheral areas, 

 the most posterior of which is larger than the others and 

 occupies the median line of the body, while the rest is 

 symmetrically disposed on the two sides. With a pair 

 of hooks imbedded in the radial spokes that bound the 

 hindmost peripheral area. Mouth subterminal and 

 ventral, with a rudimentary sucker just behind it. 

 With a paired vaginal opening on the ventral side of the 

 body. Common genital opening median and ventral. 

 With a tubular, chitinous penis. 



1. Callcotijle Mitsulcurii'\ n. sp. 

 (PI. XIX.) 

 Body very flat, ovate, about 8 mm. long and 5 mm. broad. Pos- 

 terior sucker sessile, large, having a diameter equal to about one-third 

 the whole length of the body; with seven, small notches at the 

 periphery corresponding to each radial spoke ; central area of the 

 sucker situated a little in front of the true centre of the sucker j 

 the sucker projecting beyond the posterior end of the body proper 

 by about one-third of its diameter. Hoolcs very stout, hollow in 

 its distal portion equal to about one-fourth its whole length ; strongly 

 recurved at the end ; of the form i-epresented in fig. 5, PI. XIX ; 

 0.56 mm. loug (curvature not reckoned). Anterior end of the body 

 rounded ; with two pairs of hollow, goblet-shaped stlchij glaiuls opening 

 by their long necks at the anterior end on each side of the median 



1). Dedicated to Kakichi Mitsukuri, Ph. D., Eigakuhahushi, Professor of Zoology 

 in the College of SoiencSi Imperial tTniyersity, Tokyo. 



