328 JOURNAL OF COXCHOLOGY, VOr,. I4, NO. II, JULY, I915. 



possible, this would seem a rather slender source of introduction. 



Mr. E. D. Marquand has also two specimens of P. speciosa from 

 the shell-beach of Herm, both containing the dead animal and oper- 

 culum. It should be remembered that the operculum of Pkasianelia, 

 from its peculiar construction, is less easily detachable than in other 

 genera, and there is nothing extraordinary in finding these shells still 

 containing the operculum. 



The Citlina tenclla of Jeffreys cannot fairly be considered a 

 British species up to the present. It has been dredged only in deep- 

 sea expeditions by the 'Knight Errant,' 'Triton,' and 'Lightning,' 

 but it may be discovered in the Shetland seas if any one again essays 

 that interesting region for dredging researches. It is a deep-water 

 species, and in addition to the above expeditions I can record speci- 

 mens from some soundings at the great depths of 600 fathoms off 

 Tunis, in lat. 36°© N., long. i2°o E., and near the same locality in 800 

 fathoms, in lat. 36°25 N., long. i3''2o E., soundings which were pro- 

 cured by H.M.S. 'Shearwater' when surveying those seas in 187 1. 



Lacuna divaricata var. gracilior Mete. — Achil Island. 

 L. puteolus var. expansa Jeff. — Alderney (Marquand). 



L. pallidula var. neritoidea CtouM. — Aberdeen (Simpson) ! 

 Benbecula. 



var. naticiformis Marsh. — Gareloch, a single specimen(Knight) ! 

 Dornoch Frith. 



var. imperforata INIarsh. n.var. — Shell having the umbilicus 

 wholly or partially closed. I have met with this from Guernsey only, 

 where it is the normal form. It is analogous to Z. puteolus var. clausa 

 Jeff., though in this species the umbilicus and canal are much more 

 characteristic of the type than in the latter. 



Littorina obtusata L. — Mr. E. Duprey has taken a specimen 

 at Jersey which had three eyes and three tentacles ; the centre or 

 abnormal eye was, however, double and smaller than the normal ones, 

 placed side by side on a middle tentacle, which was bifid. A further 

 development of this middle tentacle would have resulted in four eyes 

 and four tentacles. 



var. ornata Jeff. — Benbecula. Various collectors have recorded 

 this variety from the Clyde, but I have found that in most of the 

 cases (and I suspect in all) they were merely banded specimens of the 

 type. Var. palliata Say has a very close affinity to this variety. 

 Specimens from Reykjavik in Iceland are intermediate between the 

 type and var. ornata, and the three will be found to run one into the 



I ^larine Shells of Guernsey, etc.. Trans. Guern. Soc. Nat. Sci., 1901, u. 10, sep. copy. 



