Clare Island Survey — Marine Algae. 15 111 



Cladophora prolifera Kiitz. 

 One of the interesting additions to the Irish flora, and found on The 

 Bills rocks only. It is not uncommon on various coasts of southern Europe, 

 and "a single record exists for the British Isles, the plant having been washed 

 ashore in profusion at Weymouth in November, 1884 and 1885 (see Holmes, 

 " Alg. Brit. Bar.," No. 32). The Irish specimens were found in rock-pools on 

 the shady side of the islets (July, 1910). 



C. flexuosa Harv. 



The plant referred to this species was collected in pools under the shade 

 of boulders in Clare Island in July, 1910. It agrees very closely with the 

 specimens in " Algae Danmonienses " (No. 227), on which the species was 

 founded, though it is open to question whether the plant is not a form of some 

 other species. 



C. Rudolphiana Harv. 



This species, though rare in England and Scotland, is, as noted by Harvey, 

 abundant on the west of Ireland. It is Conferva Kaneana of McCalla (" Algae 

 Hibernicae "). The Clew Bay specimens agree well with Harvey's figure and 

 description, and are undoubtedly the same as his plants; but whether they are 

 identical with ft Rudolphiana, as understood on the Continent and in America, 

 is not certain. (See " Phyc. Brit.," PI. lxxxvi.) 



C. corynarthra Kiitz., var. spinescens Batt. ('00, p. 370). 



A curious plant, which appears to agree with variety spinescens of this 

 little-known species, was found amongst stones and damp soil near high- 

 water mark at the Mulranny end of Bellacragher Bay. Batters' specimens 

 were collected at Eoundstone, and occurred amongst the roots of Zostera. 

 The Mulranny habitat is a remarkable one, the more so as the plant appeared 

 to be confined to the stone-area referred to. 



C. arcta Kiitz. 

 The name ft arcta is used here in its wide sense, and includes several 

 other so-called species. Kjellmann's work, though useful, left things in a 

 most confused state. A point which has been largely overlooked is that the 

 original C. arcta in its best-known and typical forms has hooked branches, 

 though these are not so numerous as in some of the recently proposed species. 

 Many of Miss Hutchins' Bantiy Bay specimens (on which the species was 

 founded by Dillwyn) exist at Kew ; and the plant is common in England and 

 Ireland. Hooked branches are always present. In certain forms (especially 

 those in the north of Britain) the growth is less dense and the recurved 



