46 THE MARINE ALUiE OF UUERNSEY 



Cliloropliycecd are fairly well represented. The following are some 

 of these more southerly forms : — 



Oscillatoria Corallince. Cystoseira e?'icoldes. 



O. ampliihia. G. granulafa. 



Isactis plana. Taonia atomaria. 



FhcBophila dendroides, Padina Pavo7iia. 



Cladophora prolifera. Dlctyopteris memhranacca. 

 C. Hiitchinsiw and var. dlsfans. Gelldium attemiatum. 



G. rectangularis, Giymnogonyr us patens. 



G. repens. Gallymenia microphylla. 



Godiiim Bursa. Halopithys incurvus. 



Phycolapathum crlspatum. Folysiphonia opaca. 



Ectocarpus Vaillantil. P. obscu^ra. 



Myriactls pulvinata. Gtenosiplionia hypnoides. 

 Ilalopterls jilicina var. ser- Spermotliamnion irreyuUire. 



tularia. Bornetia secundijlora. 



Mesogloia Leveillei, Pleonosporlum Borreri. 



M. lanosa. Gallitliamnion hyssoides. 



Castacjnea contorta. Antifhamnion crispum. 



Petrospongium Berkeley i. Grateloupia filicina. 



Zanardinia collaris. , G. dichotoma. 



Gutleria multijida. Nemastoma dichotoma. 



Aglaozonia reptans. Litliophyllum expansum. 



Besides these there is a considerable nmnber of S2)ecies having a 

 wide range in the Mediterranean and the Atlantic. 



The following species, though occurring here and there on the 

 French and Spanish coasts, have not yet appeared farther north than 

 Guernsey : — Polysiplionia ohscura, native of Cadiz. Adriatic Sea ; 

 P. opaca, native of the Mediterranean ; Gtenosiplionia hypnoides, 

 native of Spain ; Nemastoma dichotoma, native of the Mediterranean ; 

 Lithothamnion expansum^ native of the Mediterranean. All these 

 are purely southern forms, and may possibly be considered as aliens, 

 buT; it is quite likely that their range will extend, and in the future, 

 when fully established, they may come to be regarded as part of the 

 British Flora. 



The following is a comparison of the Guernsey Flora with neigh- 

 bouring coasts, etc. : — 



There are 350 species and 78 varieties and forms of Marine 

 Algai hitherto found in Guernsey, of which 382 species and varieties 

 are common to the south of England and 333 to Ireland. There are 

 also 43 species and varieties which do not occur on the southern 

 shores of England ; 32 of them are found in Ireland and North 

 Britain, 10 being of a southern type, and one is a new species. The 

 close connection of the Guernsey Flora with Ireland and the south of 

 Eno'land is therefore evident. On the other hand, there is rather 

 more of the Atlantic element in Guernsey than in the south of 

 England, and in a certain number of cases tha southern element 

 differs slightly. Some species grow along the English coasts which 

 are wanting in Guernsey ; other species occur in Guernsey which have 

 not yet been found along the southern shores of England. 



