1914- CoLGAN. — Opistliobranch Fauna of Co. Dublin. 197 
In spite of superlicial resemblances the present species is 
distinguished from Archidoris tuber culata by many characters. 
Of these the form of the tentacles and of the anterior lamina 
of the foot are in themselves sufficient. From D. flanata 
of Aid. & Hanc. it appears to differ in little more than size 
and coloru', and it may be that Alder is correct in holding 
that species to be the young of D. testudinaria. As an Irish 
species Doris testudinaria was hrst discovered by Mr. G. P. 
Farran in the spring of the present year (in West Ireland, 
on the shores of Blacksod Bay). It is now recorded for East 
Ireland, and further exploration will probably show that it 
extends all round our shores. 
Archidoris tuberculata (Cuvier). 
Doris tuberculata. 
(generally distributed but nowhere abundant under 
rocks and stones between tide -marks ; occasional in 
dredgings. At Ireland's Eye (R. Ball & Thompson) : 
Thompson '40A. A total of 42 specimens taken in 21 shore 
gatherings at Lambay, Skerries and Dalkey, 1906-14, 
from I to 4 in a gathering ; one specimen in 2 f. Malahide 
River, 1907, another in 13 f. off Skerries, 1911, and a third 
in i4f., 1913 : N.C. 
The largest of the Dublin specimens taken was 4 inches 
long while in motion. Pure yellow forms are uncommon, 
the usual coloration being dull brown or pinkish blotchings 
on a buff ground. A pure yellow specimen was taken in 
the Malahide River attached to Halichondria panicea and 
assimilating very closely to the colour of the sponge, 
Though usually littoral, this species has been twice trawled 
at a depth of 22 f. in the Irish Sea (Farran '09). The 
radulae of seven specimens varying in length from 19 mm. 
to 60 mm. were examined. The number of rows of teeth 
was found to range from 27 to 45, while the laterals on 
either side in the widest row ranged from 36 to 70. 
The size of the egg ribbon in this species and the number 
of included embryos is very much under -stated by many 
authorities. Alder and Hancock (Monograph) found the 
ribbon to measure " when uncoiled as much as nine inches 
