152 s. GOTO. 



Professor Ijima, already named, not only for constant supervision of 

 my work, but also for lending me his books and preparations pertain- 

 ing to the subject at hand. He has also handed over to me his un- 

 finished manuscript, in which the anatomy and external features of 

 many ectoparasitic Trematodes have been made out to a great extent 

 — a circumstance f)r which I here express my warmest thanks. 



Dipl. nifponicum is very common on the gill of Carassius vulgaris. 

 Its differential characters as compared with Dipl. paradoxum are 1) the 

 smallness of the posterior suckers, 2) the greater length of the 

 posterior half of the body, 3) the shortness of the " connecting canal " 

 between the intestine and the oviduct, 4) the presence of a pair of 

 glands at the entrance of the mouth, and 5) the fact that the intestin, 

 does not present lateral branches in the posterior portion of the body. 



"Comment la reunion des Vers, a-t-elle lieu? sont-ils réunis 

 comme les frères Siamois, ou bien sont-ils ci'oisés comme les deux 

 jambes d'un X?" Hy the investigations of v. Siebold^' and Zeller,^^ it 

 has been established beyond doubt that the double animal results by the 

 union of two Diporpac in the form of a cross — a fact which had already 

 been anticipated 1)v Dujardin^^ their discoverer. The manner in 

 which the two individuals are united, and the details thereof have 

 already been made out by Zeller, who has also discussed the various 

 opinions of his predecessors, and corrected their errors. I shall 

 however, add a few remarks on some points not noticed by him, 

 some of which are perhaps peculiar to the new species. For examining 

 the external features of the worm, as well as for other purposes, it is 

 best to kill it with boihng sublimate, in a, watch-glass in which just 

 sufficient water has been placed to cover its body. The worm which 



1) V. Siebold — Ueber die Conjugation des Dipl. paradoxum. Ztschr. f. wiss. Zool. Bd. III. 

 1851. p. 62. 



2) Zeller — Untersuch, ii. d. Entwicklung d. Dipl. paradoxum. Ztschr. f. wiss. Zool. Bd. 

 XXII. 1872. p. 168. 



3) Dujardin — Histoire naturelle des helminthes. 1845. p. 316. 



