Notes on the Mari?ie Invertebrates of Rush, Co. Dublin, 231 



one of the minute forms of algae which have lately been shown 

 to perforate shells and other calcareous skeletons, and restore 

 the lime again to a soluble form. 



Amongst the Protozoa specimens of the arenaceous 

 rhizopod Haliphysema Tumanozvitzii, Bowk., were abundant, 

 growing upon Crista and Scrupocellaria. Professor Haddon in 

 his report on the Fauna of Dublin Bay 1 , has recorded this 

 species from Dalkey Island, and refers to its chequered history, 

 it having first been placed amongst the sponges, and again 

 regarded by Hseckel as the type of a distinct class. I have 

 previously found it abundant from Howth, growing upon 

 Scrupo cell aria. Some of the zoophytes were perceptibly 

 coloured by the minute green horny sheaths of the infusorian 

 Folliatlina ampulla, Mull. 



Porifkra. — The sponges were abundant, coating the sur- 

 faces of the rocks, stones, and weeds. I obtained the follow- 

 ing : — Sycon compressum, Auct., Grantia coronatunt, B. & S., 

 Leucandra nivea, Grant, HalisarcaDujardinii, Johnst., Hymen- 

 iacidon sanguineum, Grant, Halichondria panicea, Pallas, and 

 Dendoryx incrustans, Ksper. Of these Leucandra nivea is new 

 to Co. Dublin, and, so far as I can learn, to Ireland. Small 

 patches, encrusting the rocks, occurred at low water. 



In the nomenclature of the sponges I have followed Dr. 

 Hanitsch's Revision {Trans. V pool Biol. Soc, vol. viii., 1894, 

 PP- T 73 to 206). For the opportunity of seeing this I am 

 indebted to Prof. Haddon, who has kindly helped me on 

 several other matters connected with the paper. 



Hydrozoa. — I obtained upwards of twenty species of 

 hydroids, of which the following only call for notice — Atrac- 

 tylis are?iosa, Alder, growing upon Dendoryx i?icrustans. This 

 is a very minute and rare zoophyte. I have only obtained it 

 once previously from Ireland 2 . Colonies of Coryne vagitiata, 

 Hincks, were abundant amongst the sea- weeds. Campamdina 

 ttirrita, Hincks, found growing upon Campajiularia verticillata, 

 L,inn. First found by Prof. Wyville Thompson in Belfast 

 L,ough, and described by Mr. Hincks, I have since obtained 

 the species from different points of the Irish coast, but so far 

 as I am aware, it has never been collected beyond Irish waters. 



1. Proc. Roy. Irish Acad. (2), vol. iv., No. 5 (Science), p. 523. 



2. Rep. on the Hydroids of the S.W. of Ireland. Proc. Roy. Irish Acad, 

 (3), Vol. iii., No. 1, p. 140. 



