THE MYXOSPORIDIA, OR PSOROSPERMS OF FISHES. 



225 



Spore. — Eesembling Ghloromyxum dujardini; 11 /f (0-0051'") loug 

 and 7 /< (0-0034'") broad. 



Hahitat. — On Leuciscus {Squalius) grislagine L. { = Cyprinus leuciscus). 

 Tumors less common than on Leuciscus rutilus. 



It seems strange that Miiller should approximate this form to the 

 "sharp corpuscles of C. rutilus,'''' ^ asLeuckart's figure resembles much 

 more closely the elliptic form figured by Miiller (Miiller's figs. /, (j) 

 pi. 28, figs, of, g). 

 51. Myxobolus sp. incert. PI. 22, figs. 5, 6; pis. 23-25. 



* Non Biitschli. 



tLiulwig's figures seem as though they might be generalized composites based upon several of 

 Biitschli's. They may thus perhaps be not independent figures of the sporo habitant in the skin of 

 B. harhus, but have been considered to represent that form in view of its supposed identity with If. 

 miiUeri , 



Synonymy.— Both M6gnin and Lndwig, the former with doubt, the 

 latter apparently without hesitation, regard this form as identical with 

 M. miiUeri. While admitting their superior advantages (of direct 

 observation of material) I still feel considerable doubt as to the iden- 

 tity of these 2 forms, and have therefore provisionally classed them 

 separately, as, while I do not consider that there is sufficient ground 

 for a positive assertion of the distinctness of the two forms, there is 

 certainly sufticient to justify a hesitation as to their fusion. 



Megnin says the present species is probably the same as that described 

 by Robin and Balbiani as infesting the tench and carp. Now as to this : 

 (1) I am not aware that Robin ever observed such a form, and (2) the 

 spore habitant on the tench {M. ellipsoides) is, as shown by Thelohan,^ 

 unquestionably distinct from that habitant on the carp {M. oviformis). 



1 "Bei C. leuciscHs glicltcn sie ganz den spitzeu Korpercben des C. rutilus." 

 « Annal. de Microgr., 1890, ii, p. 210. 

 F C 15 



