202 Scientific Proceedings, Royal Dublin Society. 
range in space, that it is a genus of comparatively recent origin 
which will, in course of time, develop into several well-marked 
species. 
Family.—AMMOTHEIDZ. 
Genus.—PasirHox, Goods. 
Pasithoe vesiculosa, Goods. 
Thompson records a single specimen from off Dalkey Island, 
which he referred to this species. The genus is one which can 
hardly be recognised by modern authors; yet, as the form can- 
not be proved identical with any previously described pycnogon, 
I think it best to insert it, and trust that the types may be 
recovered, or fresh specimens secured, which will place its identity 
beyond doubt. From a consideration of Goodsir’s figures (15, 16), 
I would regard Pasithoe as nearly allied to Ammothea, and not to 
Collosendeis with which Sars (7) associates it. 
Family.—PYCNOGONIDZ. 
Genus.—Pycnoconum, Brinn. 
Pycnogonum littorale, Str. 
This is our commonest species of pycnogon, and there can be 
little doubt that it occurs all round the coast. It is recorded by 
Thompson from Bangor, Co. Down, and from Dublin Bay, under 
the name of P. balenarum, this name having been erroneously 
given to the animal through its confusion with the amphipod 
Cyamus, which is parasitic on whales. P. Zittorale has been taken 
at the North Bull, Dublin, and also in Dalkey Sound, by Prof. 
Haddon. It was dredged at several stations off the west coast, in 
great numbers, by the “ Fingal” :—Clew Bay, 15 fms.; Galway 
Bay (St. 21), 16 fms., sand; off Achill Head (St. 64 and 72), 
144 fms., and 127 fms. fine sand; off the Skelligs (St. 114), 80 fms. 
sand and mud. Beyond the British seas, this species is known 
from off the coasts of Lapland, the White Sea, Iceland, Green- 
land, Denmark, Germany, Holland, Belgium, France, North 
America, Japan, Chili, and Kerguelen. Its bathymetric range is 
as remarkable as its geographical extension. On our own coasts it 
has now been traced from the shore to a depth of nearly 150 fms. ; 
