l88 JOURNAL OF CONCHOLOGY, VOL. I4, NO. 6, APRIL, I914. 



not remark on any differences in their shells from the adult, while his 

 figure of D. rotundata, as also that of Forbes and Hanley, exhibit 

 their lines of growth markedly, and at no stage do they conform to 

 the obliquity of S. eddystonia. 



Again, Gwyn Jeffreys' figures of his Diodonta barleei {Diplodonta 

 rotundata juv.) agree with those of Sowerby, Forbes and Hanley, and 

 S. Wood ; they are identical with the umbonal area of adult Diplo- 

 donta, and are what one would readily concede to be the young of D. 

 roiundcita, while my figures of S. eddystonia, which are drawn fairly 

 true to form, do not appear so, nor will they correspond to the 

 umbones of D. rotundata. 



Before describing my species, the shells were seen by Dr. Boog 

 Watson, Mr. Edgar Smith, Canon Norman, and the Marquis di 

 Monterosato. The Marquis considered them "allied to Scacchia^' 

 Canon Norman pronounced them (erroneously) Kellia cydadia, while 

 the other gentlemen could not recognise the species. 



Diplodonta rotundata Mont. — Borve Bay, Barra, valves from 

 the shore (Knight) ! Rum Island, near Skye, a valve; Benbecula 

 Sound, I of., another valve. 



Cardium echinatum L. — Colour '-'yellowish-white" (Jeffreys), 

 often shaded or zoned with reddish-brown of various shades, as in 

 C. tuberculatum. A chalk-white variety comes from Paignton, but is 

 scarce ; outwardly they look like bleached shells, but all my specimens 

 have contained the animal. 



Sowerby's figure is depicted with the same sculpture as his C. tuber- 

 culatum ; it should be as Jeffreys', with the reminder that such perfectly 

 spined examples as the latter are seldom met with. 



C. tuberculatum L. — Very rare in the Channel Islands. Mr, 

 Marquand has a valve from Alderney, and also a fine perfect specimen 

 which he was assured was purchased in the Guernsey fish market. 

 Another valve was found by me at St. Aubin's, Jersey, and still 

 another valve is in the Duprey collection at the Jersey Museum. Mr. 

 Duprey cites Mr. Piquet, of Jersey, as having found C. tuberculatum 

 "living with C. echinatum some years ago" in that island,^ but I think 

 this must have been an error. 



The following records are doubtful and require confirmation — 

 Ballantrae (Knight), Stornoway fSomerville), Bute (J. Smith), and 

 Lewis (Robertson). 



The Mediterranean form (var. mediterranea Monts.) is different from 

 ours — very much smaller, more tumid and oblique, with narrower ribs, 

 and minus the spines. 



C. papillosum Poll. — Alderney (Marquand) ! A previous record 

 for Alderney by Mr. Marquand was an error for C. exigtmm var. sub- 



I Marine Shells of Guernsey, etc., Trans. Guern. Soc. Nat. Sci., looi, p. 4 (sep. copy). 



