Sladen — Echinodermata from the S.W. Coast of Ireland. 701 
Locality.— L^t 51° 1' 1^., Long. 1 1° 50' W. Depth 750 fathoms. ^ 
Remarks. — Although this example is probably immature, I feel no 
hesitation in placing it in the genus Porocidaris ; it is at once charac- 
terized by the strongly crenulated primary tubercles above the ambitus, 
and by the transversely oval, confluent scrobicules. It is distinguished 
from the previously described species by the narrow poriferous zones 
by the small number of the miliary or secondary tubercles on the 
ambulacral and interambulacral plates, and by the character of the 
primary radioles. Unfortunately, all the spines have been abraded 
from the actinal region of the test below the ambitus, and I am not 
able to say whether any of the peculiarly-toothed, flattened spinelets 
observed in other forms of Porocidaris were present in this species. 
I^one of the basal plates are punctured in this example, and I am 
unable to say, without dissection, whether the aperture amongst the 
periproctal plates between the anus and the ring of basal plates is in 
relation to the generative system. I am inclined to think it probable. 
3. Phormosoma placenta, Wyville Thomson. 
Locality — As last. Depth 750 fathoms. 
4. Phormosoma uranus, "Wyville Thomson. 
Locality — As last. Depth 750 fathoms. 
A single fine example which appears to me to accord closely with 
the figures given by Sir Wyville Thompson, ^ as well as with his re- 
marks, and with those of Professor Alexander Agassiz,^ upon the 
species. I have, however, never seen the type. 
5. JEchinus microstoma, Wyville Thomson. 
Locality. — About 56 miles off Dursey Head. Depth 345 
fathoms. 
6. Echinus norvegicus, Diiben & Keren. 
Localities. — About 56 miles off Dursey Head. Depth 345 
fathoms. Lat. 51° 1' K, Long. 11° 50' W. 
Depth 750 fathoms. 
7. Psammechinus miliaris (Miiller), Agassiz. 
Depth 5 fathoms. 
^ "Voyage of the Challenger, the Atlantic," vol. i., pp. 146-149, figs. 33, 34, 
2 Zool. Chall. Exp., part ix., Report on Echinoidea, p. 103 ; Report on " Blake '' 
Echini, Mem. Mus. Comp. Zool. Harvard, vol. x., pp. 35, 36. 
