THE DISTRIBUTION OF PADINA PAVONICA 39 



Normandie general records : 

 See Eure. 



Reports exist of attached plants immediately north of Le Havre and therefore still in Baie de 

 la Seine; frequent and dense (however ephemeral) populations seem not to commence until the 

 inner reaches of the Baie, west of the Orne Estuary. Early Calvados records are not precisely 

 located; Roussel's (1806) record (title localisation only) is the earliest traced. All other general 

 records are supported by material; although none is dated, those from Pelvet and Chauvin are 

 clearly mid-19th century. Probably these poorly documented records were all from west of the 

 Orne. None have been traced from the phycologically little-known area between the Orne estuary 

 and the Calvados eastern limit, near Honfleur. Mail & Senay (1957) included in their catalogue the 

 area west to Pointe du Hoc (near Grandcamp) because, from Fecamp to the Seine estuary, the 

 south bank of the Seine was so poorly known. We have no records localised exactly to Eure for 

 that same reason. Records listed at Eure (q.v.) are included only because they are general to 

 Normandie, or to the area covered by Mail & Senay. The south bank of the Seine, over the whole 

 of the area west to beyond the Orne, is strongly estuarine in character. The Seine itself (of immense 

 influence), the Orne, the Dives, and the Touques estuaries strongly affect local conditions and the 

 substrata are almost all mobile - sand, mud, or sand/mud/alluvium mixtures. Apart from local 

 artificial constructions, the major exception is the rocky area stretching from les Perques de 

 Villerville south for some 4 km to the northern outskirts of Trouville (Rochers des Creuniers) and 

 there is a smaller rocky beach west of Villers-sur-Mer; no previous Padina data exist for either 

 rocky area. 



West of the Orne estuary, rocks with occasional large associated inshore sandy stretches 

 commence at Lion-sur-Mer; except for short interruptions between Graye-sur-Mer and 

 Arromanches, and around Saint Laurent-sur-Mer, these are continuous to the east bank of Baie des 

 Veys (Rochers de Grandcamp). A recent detailed study of this previously well-collected area 

 (Plessis, 1961) gives more information. 



The Cote de Nacre (Orne to Arromanches) and the western portion from Arromanches to 

 Grandcamp (Bessin) form a calcareous coastline which is relatively sheltered; Cotentin Peninsula 

 reduces the effects of dominant winds from the west. Foreshores from the Orne to Arromanches 

 are wide (2 km or more) at low water. Tidal amplitude is considerable and, because the flood is 

 much stronger and faster than the ebb, sediments tend to be carried west to east, despite the Seine 

 outflow. Westward, except for the Rochers de Grandcamp, the intertidal is much narrower. 



Padina habitat requirements and periodicity are very similar throughout this area, although 

 records exist for only a few places. Luc-sur-Mer, about 10 km west of the Orne, is probably best 

 known, being the location of the Marine Laboratory, Universite de Caen. Plessis (1961) did not 

 record Padina from either the Cote de Nacre or Luc, despite studying in detail many of the rocky 

 areas, such as vhe well-known le Quihot, very near to the Laboratory and specifically mentioned 

 for Padina by Debray and (secondarily) by Cozette. 



Manche 



St- Vaast-la Hougue : 



viii.1841 (MS Lenormand), 937.150.142 (L); Chalon (1905), Herb. J. B. de Bruxelles; Hariot 

 (1912), on stones in sandy pools, summer, autumn; Herb. Buse de Brebisson, no. 360 (MS 

 Lenormand), 910.161.565 (L). 



Tie Tatihou: 



Wuitner (1911), Passage du Rhun; Hariot (1912), not very widespread at Tatihou, le Rhun, 

 near the jetty, behind the fort, summer, autumn; Wuitner (1921, 1946), passage du Rhun, 

 (Tatihou), summer, lower shore, rather common; Hamel (1939), passage du Rhun (Lebel); 

 30.vii.1965, G. T. Boalch, '. . . Present in such abundance that it crunched as we walked along the 

 causeway to Tatihou . . .' (pers. comm.); Gayral & Bert (1966), 26-3 l.vii. 1965, same meeting as 

 Boalch record above. 



