300 JOURNAL OF CONCHOI.OGY, VOL. I3, NO. lO, APRIL, I912. 



also makes this variety the larger of the two ; but the difference 

 between them is the reverse of this. I have given the extreme sizes. 



C. reticulata Brocc. — Alderney (Marquand) ! Scilly Islands 

 (Burkill and J.T.M.); Freshwater West (Span and J.T.M.); Penzance; 

 Achil Island; Clyde mouth, i8f; lona, 2of; Skye ; Gairloch ; Loch 

 Boisdale, 3of ; Pentland Frith, 35f. 



Var. asperrima F. and H.^var. formosa Jeff. — Lamlash, i8f 

 (Somerville) ! Scilly Islands, 4of.; Loch Boisdale, 3of This is 

 larger than the type — six lines by three — and the apical whorls are 

 sometimes brown, which contrasts with the snowy whiteness of the 

 shell. It was well figured and described by Forbes and Hanley, but 

 erroneously as a white variety of C. purpurea, and cited as Fusus 

 asperrimiis Brown ; but that citation, according to Gwyn Jeffreys, 

 was wrong. However that may be, Jeffreys was clearly not entitled 

 to substitute another name without justification. C. reticulata was 

 unknown to Forbes and Hanley as a British species. 



This is a widely-diffused but scarce species. I have it from only 

 a few localities, no two specimens of which agree with each other, 

 the shell differing both in shape and sculpture, the latter especially 

 varying between the two extremes of fine and coarse. Some speci- 

 mens from the Clyde are short and oval, others from Pentland Frith 

 are oblong and very finely sculptured, while the Scilly form is small 

 and slender. The latter district also produces a dwarf variety only 

 |in. in length. I have white typical specimens from Guernsey, Scilly, 

 and the Hebrides ; this must not be confused with the white variety 

 asperrima. 



None of the British forms come near the large Mediterranean one, 

 which has usually been considered the type shell, though according 

 to Monterosato^ the latter is C. cordieri Payr., the characters of the 

 embryo being specifically different. Some difficulty will be experienced 

 in determining the extreme forms of this and the last two species, 

 owing to the variability and correlation of their sculpture to each 

 other. Than all the forms of C. linearis this is more turreted, and 

 the last whorl more elongated and compressed. The young may be 

 known from its congeners by its deeper suture and the tops of the 

 whorls being angulated. Worn specimens are frequently mistaken for 

 C. ptirptirea var. lavicB, but in this the sculpture is invariably coarser, 

 and the suture more sharply and squarely excavated. Jeffreys' figure 

 is a correct representation of the British type, but that of the var. 

 asperrivia is exaggerated. 



C. purpurea Mont. — Under stones and in crevices at low water 

 of spring tides in South Devon ; usually dredged elsewhere. Fresh- 



I Nuo. Riv. Conch. Med., p. 44. 



