1907 Stelfox & Milne. — Cork Conference. — Mollusca. 287 



this Pisidium plentiful, and a few fairly large specimens were 

 taken, though none reached the dimensions of Dr. Scharff s 

 examples. In this lough we found a very thin species of 

 Limnaea, resembling L. involuta va. texture and size, only even 

 more delicate and perhaps a little larger than that .species is 

 usually met with. The shell practically consists of epidermis, 

 and like L. i?ivoluta is beautifully and regularly striated in the 

 line of growth. The intortion of the spire is not quite so pro- 

 nounced, though in some of the specimens taken, this is 

 distinctly sunk. The animal in both colour and markings is 

 very similar to L. involute/, and L. peregra, but when in motion 

 its habits show some striking peculiarities. It moves very 

 rapidly and carries its shell in a jaunty fashion, often pausing 

 to twist the shell quickly from side to side, as if trying to 

 shake off some imaginary enemy. (See Messrs. Chaster 

 and Collier on L. i?ivoluta, LN.> Sept., 1898) In both its 

 carriage and manner this mollusc is like a member of the 

 Physa group, as besides its rapid and peculiar movements, 

 the body is much further extended from the shell than in any 

 other Limnaea we have seen, with the exception of the animal 

 in L. involuta. It is probably this latter fact that led our 

 early conchologists to place L. involuta under the genus 

 Amphipeplea. Unfortunately time has not permitted Mr. 

 J. W. Jackson, of Manchester, to investigate the anatomy of 

 this Limnaea, but we give below the opinion of three of our 

 most eminent conchologists, based on the external characters 

 of the shell. Dr. Scharff considers that though closely allied 

 to L. involuta it may be a distinct species. Mr. J. W. Taylor 

 is inclined to believe that it is nearer to L. Burnetii, while 

 Mr. A. S. Kennard puts it down as true L involuta. With the 

 last identification we are inclined to agree, but it is better 

 to wait until the animals have been dissected before coming 

 to any definite conclusion. On our homeward tramp we paid 

 a short visit to Lough Namaddra and again we found Pisidiu?n 

 hibernicum common, but there was no trace of the Limnaea, 

 though it may occur, as in Lough Nagarriva we only noticed it 

 in one corner of the tarn and might easily have overlooked it, had 

 not the finding of a dead specimen warned us to keep our eyes 

 open. We give below a list, which comprises a few species 

 not recorded in Mr. Standen's report on the Kenmare Confer- 

 ence of 1898, and also new localities for already recorded 



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