i897] 241 



THE HYDROIDS OF VALENCIA HARBOUR, 



IRELAND. 



BY EDWARD T. BROWNB, 

 (University College, London). 



In the Irish Naturalist (May, 1896), there is an article " On 

 Shore-collecting and Dredging" in Valencia Harbour by my 

 friend and colleague, Mr. F. W. Gamble. In that article Mr. 

 Gamble gives the names of the Hydroids which were found in 

 the harbour, but the identification of the species was done by 

 myself, though most of the specimens were collected by Messrs. 

 Gamble and Beaumont. The name of Coryne pusilla must be 

 withdrawn from the list, as a subsequent examination of the 

 specimens show they are not to be distinguished from Coryne 

 vaginata. A second visit to Valencia Harbour was made last 

 year (1896), and a few more species were found. It is my 

 intention to give now a list of all the Hydroids which we 

 found, and a brief description of some of the specimens. 



From the situation of Valencia Harbour, its large area, its 

 sheltered position, and the varied nature of its shores, it 

 would be expected to yield a considerable hydroid fauna. 

 The tow-net captured several species of Medusae which are 

 known to be derived from hydroid colonies, but the Hydroids 

 themselves we failed to find, though much dredging and 

 shore-collecting were done, especially during our second visit, 

 when we had a sailing-trawler for dredging in the deeper 

 water outside the harbour. The Hydroids turned out to be 

 poor in the number of species and below the average compared 

 with the other groups of animals, and only a few species were 

 found in abundance. To judge from the abundance of certain 

 species of Medusae there must exist colonies of Hydroids, 

 covering large areas, not far from Valencia, but the frequent 

 dredgings did not reveal to us their grounds. The absence of 

 certain Hydroids. though their Medusae may be abundant, I 

 have noticed in other localities. It appears to me that a 

 distinct hydroid fauna probably lives upon rocks lying in a 

 moderate depth of water not far from shore. Such places the 

 dredger avoids as much as possible from the fear of tearing 

 the net or losing the dredge. 



