230 The Irish Naturalist. 



Station for tea. Some had been left behind at Rathmullan, 

 to revisit Port Salon neighbourhood, whilst others remained 

 over the Sunday in Deny, but the bulk of the members 

 returned home in the exquisite evening light, cordially 

 agreeing that it had been a most charming and successful 

 trip amongst enchanting scenery. 



NOTES ON THE MARINE INVERTEBRATES OF 



RUSH, COUNTY DUBLIN. 



BY J. K. DU3RDKN, A.R.C-SC. (L,Ond.) 



The following notes are based principally upon the material 

 gathered on the excursion of the Dublin Naturalists' Field 

 Club to Rush and Skerries on the 8th September, 1894. The 

 excursion was organized for the purpose of studying the 

 marine fauna and flora of this portion of the Dublin coast. 

 So far, few collections have been recorded from the district. 

 Owing to the fact that it was low water about noon, and that 

 the party, following out the programme arranged, could not 

 reach Rush before three o'clock, I found it desirable to go by 

 an earlier train, and was thus collecting on the shore before 

 the tide turned. I devoted the time to the rock-pools a little 

 north of the harbour at Rush. Here the Upper Carbonifer- 

 ous Limestone crops out at a considerable angle, the direction 

 of the strike being almost at right angles to the shore. 

 Many rock-pools occur here. These are occupied largely hy 

 algae, amongst which, and along the sides of the rocks, I found 

 a moderately rich fauna. I again visited the place during the 

 next spring tides and added a few specimens to those collected 

 on the excursion. On this occasion I confined my attention 

 to the rocks a little north of the martello tower. 



The sides and stones in some of the rock-pools were coated 

 with the red calcareous alga Mclobcsia and the pink Litho- 

 thamnion polymorphism. Many of the zoophytes, especially 

 Obelia and Fhistra, were of a bright red colour, due, as I was 

 informed by Prof. Johnston, to the presence of Rhodochorton 

 mcmbranaceum, a red alga only recently added by him to the 

 Irish flora. The calcareous spicules of one of the_sponges 

 examined (Lcucandra nivea, Grant), were already attacked by 



