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On Metopidia pterygoida, a New Rotifer. 



By M. F. Dunlop, of Greenock. 



Communicated by C. F. Rousselet, F.R.M.S. 



{Read January 15th, 1897.) 



Plate XVII. 



At the end of July last, when leaving the Island of Arran 

 (Scotland), where I had been enjoying a few weeks' holiday, I 

 brought with me from a small mossy pool, in a Moorland district 

 about 500 feet above the level of the sea, a gathering which I 

 intended to examine carefully at home. I was unable to 

 investigate the gathering till September, when I found in con- 

 siderable numbers a Rotifer which I take to be Stephanops 

 longispinatus. I had shaken, in a large cell, a spray of 

 sphagnum, where Stephanops seemed to congregate, and was 

 watching the sprightly Rotifer when I noticed a strange form 

 smoothly and slowly gliding out from the moss, and then in 

 like manner moving back to what appeared to be its favourite 

 haunt. On the stranger emerging again, instead of studying its 

 behaviour and getting an idea of its form from different aspects, 

 I anxiously dipped out the then only visible specimen in case it 

 should be lost amongst the debris, and proceeded to mount it. 

 But, alas ! on letting down the cover glass the minute speck 

 slipped on to the ring of the cell and, to my great disappoint- 

 ment, was crushed. Another search brought to view a second 

 specimen, which was nervously dipped out and speedily mounted 

 in the expectation that I should surely find another for observa- 

 tion. But while the Stephanops, after the lapse of nearly five 

 months, continues in evidence, I have failed to get another 

 specimen of the " stranger "—not even a lorica ! This is 

 unfortunate, as details which might have been obtained from a 

 lateral and ventral view cannot be given. 



All who have seen the mounted slide — including Mr. Hood, 

 Mr. Dixon-Nuttall, and Mr. Rousselet— agree that the new 



