65 



JOURNAL OF CONCHOLOGY. 



Vol. 14. JULY, 1913. No. 



ADDITIONS TO "BRITISH CONCHOLOGY." 



By J. T. MARSHALL. 

 Part VII. {continued from p. J5). 



Aplysia punctata Cuv. — Between tide-marks during the spring 

 months, when this species resorts among the seaweed-covered rocks 

 for spawning, and may then be met with in large numbers, though 

 their visits are capricious and their numbers varying. In Jersey, 

 where an enormous extent of rocky coast is uncovered at low water, 

 they may in some seasons be estimated at millions ! I have found 

 the fry in dwarf sea-weeds during August and September; in October 

 these had attained half-an-inch in length, with shells a line long. 



The shell consists of two layers, which in this species are both 

 horny, except in aged specimens or to repair fractures, when they 

 are semi-calcareous ; while in A. depilans, which it resembles, the 

 inner layer is shelly, very fragile and brittle, and easily shed. The 

 largest come. from St. Mary's Flats, Scilly, and measure i^in. by i|in. 



The animal is an easy and very interesting subject for dissection. 

 After making an incision and removing the shell, the whole of the 

 nervous system is exposed to view, and may be readily lifted out 

 intact for examination. 



A. depilans L. — A very rare visitant to Guernsey and Torbay. 

 In the former locality solitary specimens are obtained at wide inter- 

 vals; but in Torbay a small fleet arrived in 1875, and lingered for a 

 couple of years, but failed to establish itself, though the temperature 

 and position of Torbay would seem fairly promising for its acclima- 

 tisation. Previous to that only one specimen had been found there, 

 by Mr. P. H. Gosse. Landsborough and Kennedy have recorded it 

 from the Clyde district, but their identifications are extremely unlikely. 



The shell of A. depilans differs from that of A. punctata in being 

 three or four times the size, lighter in colour, thinner, and much less 

 convex or boat-shaped. It will not bear much handling, and if not 

 extracted from the animal with the greatest care the internal shelly 

 layer breaks up into minute fragments, and the external horny one 

 curls up out of all resemblance to its natural shape. The dye from 

 the animal is a pale to a deep purple, according to the more or less 



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