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SUPPLEMENT TO THE BRITISH 



1. Discina Atlantica, King. Dav., Supplement, PI. I, figs. 11, 11 a, 11 b. 



'Proceedings of the Natural History Society of Dublin,' 1868. 



This species is described by Prof. King as " Corneous, brown, thin ; rather prominently 

 conical ; marginal outline approximately circular ; sides scarcely convex ; two and a half 

 sixteenths of an inch in diameter, and one sixteenth in height ; apex subcentral, and on 

 the posterior half; outer surface, as seen with a good pocket lens, crowded with fine, 

 regular, subparallel, concentric, raised lines ; inner surface showing, under a high 

 magnifying power, a delicate, scaly, or imbricated appearance ; anterior portion of a 

 yellowish-white colour ; muscular impressions well marked." 



Four examples of the upper or unattached valve only of this minute shell have been 

 obtained. One, the joriginal specimen, was taken by Capt. Hoskyn attached to the 

 sounding lead off the " Porcupine Bank," on the west coast of Ireland, at a depth 

 of 1240 fathoms. The second was dredged by Mr. Jeffreys in nearly the same place 

 and 1366 fathoms. The two remaining examples were found by Sir James Anderson, in 

 the North Atlantic, when fishing up telegraph cable, in more than 2000 fathoms depth. 



I have carefully examined all the specimens, and am confident as to the correctness of 

 Prof. King's generic indentification j the corneous nature of the shell and shape of its 

 muscular impressions would preclude the possibility of its being referred to the genus 

 Crania. 



2. Crania anomala, Miiller. Dav., Tertiary Mon., PI. I, fig. 1. 



Crania anomala, Forbes and Hartley. British Mollusca, pi. Ivi, figs. /, 8. 



— — Jeffreys- ^rit. Conch., vol. ii, p. 24, pi. i, fig, 3, and vol. v, pi. xix, 



fig. 6, &c. 



This well-known species, stated by Mr. Jeffreys to occur on almost every part of the 

 Scotch and Irish coasts, is abundant at Oban, in Loch Fine, the Orkneys, Isle of Man, &c. 

 The depth at which it is found varies considerably. Thus, off the west coast of Ireland 

 it occurs at depths of 90, 150, 670, and 808 fathoms. Between Shetland and Faroe Isles, 

 at 200 to 250 fathoms ; north of Hebrides, 170 to 530 fathoms (Carpenter and Thomson). 

 It is very abundant in seas of other parts of the world. 



