I0I4. COLGAX. — Ophfhohrayich Fauna of Co. Dublin. 105 
noticed. Their tips were quite smooth-edged, though 
in the younger and smaller individuals (^7) and (ft), they 
were sharply denticulate. The mandible-edges, armed 
with a row of tubercles in the smaller specimens had, like 
the uncini, become quite smooth in the large specimen. 
Tritonia Hombergii (Cuvier). 
Rare. " A specimen about 4 inches in length, with 
the examination of which I have been favoured by Mr. 
Ball, was dredged with oysters some years ago at Howth " : 
Thompson, 40 A. A single specimen in deep water, Dublin 
Bav : H assail '42. One specimen in 10 f. 6ff Bullock: 
r olgan, '08 — this specimen lived in captivity for more 
than a month, feeding on Antenmilaria. Taken in associa- 
tion with Alcyoniiim digitatum in two hauls in 14 f. off 
Church Island. Skerries in July. 1913, a total of three 
specimens, i mature. 92 m.m. long, the others juvenile, 
nearly pure white and from 10 to 15 m.m. long. 
In the large Skerries specimen the buccal mass was found 
to be of relatively enormous size, measuring fully 18 mm. 
X II mm., and occupying nearly one-third of the body 
cavity. The radula had 70 rows of teeth, the widest 
having 220 uncini in each half row. The coarse serrations 
of the mandible-edges in this specimen were not simple, but 
made up of aggregations of smaller teeth which in the 
younger specimens were arranged in several rows as in tlie 
adult T. plchcia. 
T. plebeia (Johnston). 
Rare. Four specimens, the largest 18 mm. in length, 
found nestling at the foot of a large mass of Alcyoninm 
digitatum attached to an old Pecten shell dredged in 14 f. 
off Church Island, Skerries, July 27th, 1912 : Colgan, '13A. 
Three specimens, the largest 20 mm. in length, dredged in 
almost the same locality as the preceding in July, 1913, in 
a dredging which contained many specimens of Alcyonium 
digitatum. 
