Mackintosh — On Irish Zoopyhtes. 57 



yielded a number of specimens of Port, pusilhis, Ehalia pennantii, 

 Atelecyclus heterodon, Porcellana longicornis, and of course Paguri in 

 abundance. On one occasion, when the sea was particularly smooth, I 

 noticed several large shoals of the Megalopa stage of some crab, but of 

 what species I do not know. I also observed a curious habit on the 

 part of the shore crab which was new to me. A few miles south of 

 Greystones there is an inlet of the sea which breaks up into a number 

 of small branches ramifying over a considerable area, and of course 

 rising and falling with the tide. In the larger channels are to be 

 found sand-dabs in considerable numbers, and in the smaller channels 

 I was surprised to see a good many specimens of the shore crab living 

 side by side with numbers of gudgeon. The water in the main 

 channels was, so far as I could judge, fairly pure sea water, that in 

 the smaller channels was brackish ; the communication with the princi- 

 pal channels was in many cases rather obstructed, and in this way I 

 presume the addition of rain water from time to time rendered it brack- 

 ish, the freshwater fish (which probably found their way in from some 

 neighbouring ditch) and the marine crab becoming gradually accli- 

 matised. Bell, in his ^' British Crustacea," alludes to the fact that 

 the shore crab will survive immersion in fresh water, a power which 

 apparently enabled the specimens I saw to resist the effects of the 

 change from sea water to brackish water ; their colour was exactly 

 that of the sandy mud on which they lived. 



Vermes. — My list of representatives of this sub-kingdom is very 

 meagre, with the exception of Polyzon, of which I have obtained a 

 good collection, but details of which I reserve for a future Paper. Of 

 the Tunicata the best examples were obtained tolerably near the shore, 

 where great masses of Botryllus violaceus were very abundant ; Apli- 

 dium fallax was fairly frequent, and Listoma ruhrmn rather scarce ; 

 Ascidia canina and Phallusia intestinalis were also common, but of 

 small size. The only other group of which examples were noticed 

 were the Chcetopoda, represented by Aphrodite aculeata of small size 

 and very dingy colouration ; Polyno'e squamata, Nepthys margaritacea, 

 Terelella medusa, Serpula triquetra, and Spirorhis communis. A small 

 piece of empty tube, probably belonging to a species of Pectinaria, was 

 also obtained. Doubtless many others occurred in sea-weed, but I did 

 not search for them. 



Echinodermata. — As regards numbers this is the most abundant 

 group, for Brittle stars were taken up simply by the dredge-full, and 

 of th.e most exquisite beauty I have as yet seen. The species observed 

 were : Comatula rosacea (scarce), Ophiura texturata, Oph. allida (both 

 rather scarce), Ophiocoma neglecta (scarce), Ophiocoma granulaia (not 

 very common, but of remarkably large dimensions, and finely coloured, 

 the disc being frequently marked with an orange star on a chocolate- 

 brown ground^), Ophiothrix rosula (this species occurs in prodi- 



1 Forbes (Brit. Star-fishes) remarks that a variety of an orange colour is not un- 

 common in the Irish Sea. 



K.I.A. PROC, SER. ir., VOL. IT. SCIENCE. I 



