155 



Notes on Rotifers, with Description of Four New Species, 

 AND OP THE Male of Stephanoceros Eichornii. 



By Geo. Western, F.R.M.S. 



Plate IX. 



{Read October 2lst, 1892.) 

 Pleurotrocha grandis=Diglena jerox. 



In April last year I described a Rotifer which I find in the 

 river Wandle, and which is unmentioned by any of the author- 

 ities, I then doubtfully assigned it to the genus Pleurotrocha, 

 chiefly on account of the absence of eyespots. Since the 

 publication of my note on the subject, which, with Mr. Chap- 

 man's figure of the Rotifer, will be found in the Journal of this 

 Club for July last, I have had opportunities of examining speci- 

 mens of Diglena rmistela, which it very closely resembles, and 

 have come to the conclusion that it would more properly be 

 classed along with that species. Mr. Gosse did not consider 

 that the absence of eyespots excluded that species from the 

 genus Diglena, and therefore I see no reason why mine should 

 not also be admitted. There is already, however, a Diglena 

 grandis, and to prevent confusion it is necessary to change the 

 specific name also. In future I propose to call this Rotifer 

 Diglena ferox. 



Pterodina on Asellus vulgaris. 



It may be remembered that when Mr. Parsons described a 

 new species of Pterodina which he had found living com- 

 mensally on Asellus, and which he named Pterodina cceca, 1 

 mentioned that in seeking for that Rotifer I had also found the 

 P. truncata of Gosse, and, as I then thought, more than one 

 other species. Having since pursued this subject with some 

 care, I have arrived at the conclusion that I have really met 

 with but three species, viz. : — Pterodina coica. Parsons; P. 

 truncata, Gosse, and P. elliptica of Ehrenberg. The great 



