THE DISTRIBUTION OF PADINA PAVONICA 43 



fetch from the west. Especially in the west, there are more sheltered sandy stretches abutting rocky 

 platforms, in bays protected by headlands or other offshore reefs, than in Alderney. The north- 

 west of the island, Cobo to L'Ancresse area, has the lowest rock/sand shores, providing records of 

 Padina. The much larger number of records for Guernsey is not simply due to greater abundance. 

 Guernsey has been a more generally visited island, by virtue of its larger size, easier accessibility, 

 more accommodation, and greater variety of habitat. Marquand, who lived and worked in the 

 Channel Islands, was responsible for the large majority of earlier original data from Guernsey. 



Sark: 



Rocks of Sark are all very resistant to marine erosion; the coasts remain steep and access is 

 difficult. Phycologists have sufficiently frequently visited the island, so that the failure to record 

 Padina must be due to the predominance of steep, very wave-beaten shores, with a general absence 

 of detrital conditions over platforms in shallow standing water. Persistent examination of locally 

 less wave-beaten sites would probably eventually detect plants. 



Herm: 



Few marine algae have been recorded from Herm; all Padina records date from the joint 

 British-French Field Meeting, September 1960. Davy de Virville (1963 : 28-34) described the 

 island, indicating that although the southern part is formed from granite and hornblende cliffs, 

 the north is lower and sandy, with dune formations. Shell Beach, in the north-east, is about 700 m 

 long; less directly wave-beaten than elsewhere, it is still affected by strong currents. The north of 

 the west coast is relatively sheltered, with coarse sandy areas abutting sporadic rocky outcrops. 

 Guernsey provides shelter from fetch, so that the effect of wave-action is not great. Shell Beach 

 side, with coarse shell sand, shows a relatively poor flora, but at the south end, where it abuts on 

 rocky areas, there are small pools with Padina. 



Jersey : 



This, the largest island of the group, is even more exploited for vacation purposes than 

 Guernsey and has the longer history of phycological work. The earliest Padina records are mostly 

 30-40 years before those of Guernsey. All Jersey coastlines but the north have vast tracts of sandy 

 beach uncovered at lower waters; even on the north coast, which is steep and forbidding, there 

 are some small sandy areas. Amongst the larger tracts, St Ouen's Bay, Greve d'Azette, and St 

 Clements Bay possess considerable areas of relatively low rocky platforms and reefs that abut or 

 emerge through the sand, providing classical habitat conditions for Padina. The smaller sandy 

 locations on the north coast also involve characteristic sand/rock transition areas; amongst these, 

 Greve de Lecq actually has mid- 19th century records of Padina. 



Les Ecrehous and similar rocky groups in the Golfe Anglo-Normand: 



Many such groups (e.g. les Casquets; Jethou; Brechou; les Ecrehous; les Minquiers; lies 

 Chausey; Grand Lejon; Barnouic; Roches Douvres; and les Dirouilles) exist in the Golfe. No 

 records of Padina exist for most of these, probably due to a lack of sufficiently long-term or frequent 

 collecting visits, although some smaller rock groups undoubtedly lack the required habitat 

 conditions. lies Chausey, for which there are many records, have already been dealt with (see 

 Manche); only for les Ecrehous, of the remainder, are there published records. Les Ecrehous is a 

 rock group midway between the north-eastern point of Jersey and the Manche shores at Cap de 

 Carteret. Les Minquiers, Grand Lejon, Roches Douvres, Jethou, Brechou, and les Casquets, at 

 least, have been visited by phycologists (Fischer-Piette, 1932; Davy de Virville, 1963) without 

 Padina being recorded. Few Padina records from the Channel Islands are dated to day and month. 

 Those that are show the same bias towards [July], August, and September as is general for northern 

 areas within the P. pavonica range. Davy de Virville (1963 : 56), in a brief summary of the relation- 

 ship of the Channel Island marine flora with that of the adjacent French coasts, stated: '. . . des 

 especes a affinite meridionale, comme Padina Pavonia, y sont plus rares'. 



