252 



NOTES ON THE NON-MARINE MOLLUSCA OF 

 MORTEHOE. No. 4. 



By M. jane LONGSTAFF, F.L.S., F.G.S. 



(Read before the Society, January 14th, 1920). 



Since my last communication in January, 191 2, I have not been able 

 to do much collecting in this district, and the additions to previous 

 lists consist chiefly of varieties which are perhaps worth recording for 

 the sake of making the record as complete as possible. 



Helicella virgata (Da Costa) var. near niaritima Drap. 



Var. minor (Taylor) (albicans Grat.) Also a monstrosity (var. 

 albicans) with the earlier part of the spire raised and partially detached 

 from the body-whorl. These were all found on the Golf Links, 

 Woolacombe, and were examined by the late Mr. W. D. Roebuck. 



Clausilia bidentata (Strom) var. albina Moq. — Garden wall, 

 Twitchen, Mortehoe. 



Acicula lineata (Drap.). — Ossaborough, Mortehoe, among dead 

 leaves in a wood. This record is interesting on account of its being 

 only the second specimen taken in the parish. 



Sphserium lacustre (Miill.). — Pond in Gratton Quarry (a field 

 name). In September; 1909, 1 found but two specimens here though 

 I searched for some time. I did not go there again till June, 1918, 

 and then I noticed that the species had multiplied considerably, being 

 very abundant both in the pond itself, and also on the mud left damp 

 at the edge by the shrinkage of the water. None of the shells were 

 as large as those previously taken. I sent some examples to 

 Mr. J. W. Taylor and he stated that he considered them to be the 

 " variety rycklioltii (Norm.) though possibly not perfectly character 

 istic." The umbos are not so large as in the specimens of this variety 

 from Damage pond. Gratton is separated from the latter by higher 

 intervening land, and while Damage has a stream running through it, 

 Grafton is a mere quarry pit with neither inlet or outlet. At my first 

 visit I did not observe any other molluscs associated with this species, 

 but this time I found Liinncea truncatula (Miill.) in numbers. 



A Colony of Limax flavus var. tigrina Pini, at Reigate. —During the 

 last few weeks numerous examples of this striking form have appeared in my 

 scullery at Reigate, having entered by the sink pipe. The markings are typically 

 black, and form a continuous line on each side of the mid dorsal surface which is 

 clear yellow, but the dark colouration varies in intensity in different individuals 

 from black to the normal typical grey. In the same colony the markings typically 

 distributed vary in different individuals from black to the typical grey. Some 

 individuals answer lo the description of var. uinbrosa, Philippi. — Lionel E. Adams 

 {Read before the Society, November 2nd, 192 1). 



