On the Dendritic Appendage of the Urogenital 

 Papilla of a Siluroid. 



By 

 S. Hirola, Rigakushi.^ 



Zool. Inst., Science College, Imp. Univ., Tokyo. 



With Plate XXXn. 



In spite of the fact that all the siluroid fishes included in the 

 genus Plotosus have long been known to possess a peculiar dendri- 

 form appendage behind their urogenital papilla and that its external 

 features have repeatedly been described, only imperfect knowledge 

 exists of its internal structure and physiological significance. It 



* It is uiy painful duty to record here the death of the author of the present article. Some 

 time before his last illness, Mb. Hirota placed in my hands the manuscript of the article, 

 which had already Ijeen so far worked over that after his death, I found myself able to put them 

 into the final shape for publication. The alterations that I have taken the liberty of making 

 are only such as in my opinion bring out his ideas more clearly and would, I believe, have 

 been accepted by him if he had been alive. In no case have I wittingly run counter to his ideas. 

 At the same time I must ask the reader's kind consideration of the circumstances if some 

 parts are found to be not as full as may seem desirable. I can not let this opportunity pass 

 without saying that we have lost in Mr. Hirota a co-worker of great promise. His published 

 articles besides the present one are as follows : — 



1 . On the Sero-Anmiotic Connection and the Foetal Membranes in the Chick. Jour. 



Coll. ScL, Imp. Univ. Japan Vol. VI. IS94. English. 



2. On the Fauna of the Ogasawara (Bonin) Islands. Zool. Marj., Tokyo, Vol. VI., Nos. 



68 and 69, for June and July, 189a. Japanese. 



3. On the Loss of Weight in the Fowl's Egg during Incubation. Zool. Mag. Tokyo, 



Vol. VI., No. 71 for Dec. 1894. Japanese. 



4. Anatomical Notes on the ' Comet ' of Linckia multifora, Lam. Zool. Mag. Tokyo, 



Vol. VIL, No. 78 for April 1895. Japanese and English. 



5. Xotes on a Scink with an Accessory Tail. Zool. Mag. Tokyo, Vol. VII., No. 81 for 



July 1895. Japanese and English. 

 Besides these, he published several short notes in the Zoological Magazine of Tokyo. 

 Zool. Inst., Sei. College, Imp. Unii: Tokyo. 



K. MiTSUKURI. 



