of the North of Ireland. 85 
and from Dickie’s lists it would appear to live in profusion in Strangford 
Lough. 
Trochus cinerareus, Linne. 
One of our most common species, living on stones and sea-weed between 
tide-marks and in depths up to 25 fathoms, throughout the province. 
Hyndman dredged a single living specimen in the great depth of 70-90 
fathoms off the Maidens. It is locally called “ silver- shell,” on account of 
the pearly lustre of the inner layers. The T. littoralis, Brown, for which 
Thompson, quoting from an older writer, mentions Killough as a station, 
belongs to the present species, and, according to Jeffreys, can scarcely he 
considered a variety. 
Trochus umhilicatus, Montagu. 
Between tide-marks, among stones and Fuel ; common. 
Trochus Suminyi, Requien. 
Our rarest shell, Bundoran in Donegal Bay being its only British habitat. 
It appears to be of rather rare occurrence there, where it was first discovered 
some years ago by Edward Waller, an assiduous and distinguished Ulster 
conchologist. 
Trochus lineatus, Fa Costa. 
“This littoral species, found on rocks, stones, &c., is unknown to me 
further north on the Eastern line of coast than Ballywalter, Co. Down 
(54^° lat.). Southward it is common ” — Thompson (sub Monodonta crassa). 
On the western side of the province it flourishes at Bundoran, in just the 
same latitude — Waller, Jeffreys, and others. 
Trochus Montacutl, W. Wood. 
Sparingly hut widely distributed on the Antrim and Down shores. Hynd- 
man dredged it alive off Ballygalley Head, Waller off Groomsport, and Dickie 
in Strangford Lough and the open channel adjoining — depths ranging from 
12 to 25 fathoms ; in a dead state it occurred frequently, especially on the 
Turbot Bank (sub T. Montagui). A very elegant scalariform monstrosity was 
dredged off Larne, as noted by Hyndman and Jeffreys. 
Trochus striatus, Linne. 
“Dead, in Turbot Bank sand, Mr. Jeffreys ’’—Hyndman, 1859 Report; 
specimens from that locality are in the Belfast Museum Collection. In his 
“British Conchology,” the most northern station which Jeffreys gives is 
Dublin Bay. It is a southern species, and frequents the Channel Islands and 
south coasts of England and Ireland. 
[Trochus exasperatus, Pennant. 
“Turbot Bank, Dr. Dickie, doubtful”— Hyndman, 1857 Report (sub T. 
exiguus ). This is the only note of the occurrence of the present species. 
J effreys regards as doubtful all localities other than those on the South of 
England coasts and Channel Islands.] 
