﻿Notes upon a Haplosporiclian. 



175 



XVI. Notes tcpon a Haplosporiclian helonging to the genus 



Icthyosporidiiim. By Muriel Eobertson, Carnegie 



Research Scholar in the University of Glasgow, 

 [Plates IX. and X.] 



(Eead 16th December 1907.) 



In December 1905 MM. Caullery and Mesnil embodied 

 in an interesting memoir^ all the knowledge on the Haplo- 

 sporidia so far forthcoming. They divided the order into 

 three families — (1) Haplosporiidce, (2) Bertramiidce, (3) 

 Coelosporiidce, and a fourth group containing forms of 

 doubtful affinities. It is to the second of these families, 

 namely, the Bertramiidse, that the parasite I wish to 

 discuss belongs. 



Caullery and Mesnil created the genus Icthyosporidiuni 

 for two tissue parasites, Ictliyosporidium g aster ophilum and 

 Icthyosporidmni phymogenes, which they found in certain 

 fishes, and placed the genus provisionally in the family of 

 the Bertramiida3. There is, as far as I can see, no reason for 

 removing the genus from this family. The present parasite 

 belongs undoubtedly to the genus Icthyosporidiuni, but 

 although closely allied to Icthyosporidiuni gaster ophilum, it 

 does not completely agree with either of Caullery and 

 Mesnil's two species. The differences between this parasite 

 and Icthyosporidiuni g aster ophilum will be summarised later 

 on in this paper. 



One hesitates to create a new species, more especially 

 when dealing with incompletely known forms. I therefore 

 propose to place the parasite in the genus Icthyosporidium, 

 while leaving the species name on one side. Future in- 

 vestigation of this little known group will settle the 

 question of separate species much more satisfactorily than 

 can be done in the present state of our knowledge. 



The parasite was found in large quantities in the liver 

 and in the wall of the alimentary canal, and also in the 

 mesentery of a small flounder in January 1906. The flounder 



1 Arch. Zool. Exp., T. iv. No. 3. 



