196 PROCEEDINGS OF THE MALACOLOGICAL SOCIETY. 



Iceland, practically all of which island lies sonth of the Arctic Circle. 

 The surface temperature of the water on the north coast of Iceland 

 appears never to rise above 41° F., while in winter it sinks to 32°; 

 the water on the south-west of Iceland is never colder than about 40°, 

 and in summer rises to between 50° and 60° F. 



Mohr (89), G. 0. Sars (105), Verkruzen (119), Johansen (55), all 

 record the occurrence of the species in Iceland. My collection 

 contains specimens from Keykjavik, the Islands of Vithey, Hafnafiord, 

 Stykkisholmr, and Flatey Island in the Breidifiord, Dyrafiord in the 

 extreme north-west, as well as from two places not marked in my 

 maps, Skerjafiord (H to 2 fathoms, sandy bottom, A. C. Johansen) 

 and Heymaey (A. C. J.). In form the specimens vary greatly, some 

 being stout and thick-lipped, and recalling forms from our own coasts, 

 some (from Reykjavik) thin-lipped and rather degenerate, colour 

 a peculiar slaty-grey, interior strongly iridescent, others, from the 

 Breidifiord, resemble a form from Vadso, while those from the 

 Dyrafiord, the furthest north, closely recall a form described above 

 fi'om the Mourmane coast. 



Specimens from the Faroe are large and very solid : the broadly 

 banded form also occurs there (Coll. A. H. C). The species is in 

 Morch's catalogue (86). 



In the British Islands, which appear to be the metropolis of this 

 species, it occurs in abundance in every form of coast on which it can 

 find a lodgment. 



Locard (71) gives the following compreliensive list of French 

 localities: — Kngiish Channel: Dunquerque (Le Nord) ; Wimereux, le 

 Boulonnais (Pasde Calais) ; Dieppe, Fecamp (Seine Inf.) ; Normandy ; 

 Langrune, Granville (Calvados) ; Cherbourg, Valogne (La Manche) ; 

 St. Malo, Cancale (lUe et Vilaiue). Atlantic Ocean: Armorican and 

 Aquitanian regions : Brest, lloscoff (Finistere) ; Impairs, Pouliquen, 

 Ker Cabalec, Pornichet (Loire Inf.) ; He d'Yen, Sables d'Olonne (La 

 Vendee) ; La llochelle, lloyan. He de Be (Charente Inf.) ; Cordouan, 

 Vieux Soulac (Gironde) ; St. Jean de Luz (Basses Pyrenees). The 

 var. iinbricata, Lam., is given by the same author as occurring at 

 many places from Dunkirk to Koyan. In reviewing a collection from 

 French localities one is struck by the marked declination in size of 

 shell as compared with specimens from our own shores, and this ia 

 particularly the case with specimens from the Atlantic coasts. Shells 

 are massive and well formed, but they do not appear to approach ours 

 in length. The var. imhricata seems to be relatively abundant. 



On the northern coasts of Spain, P. lapillus is recorded from 

 Santander, San Vincente de la Barquera, and Gijon (Hidalgo 45, 47), 

 from Asturias and Galicia generally (Mc Andrew 74), from Bio de 

 Betanzos and Corunna (Hidalgo 45 and Mc Andrew and Woodward 

 78), from Vigo (Hidalgo 45 and McAndrew 74, 75), from Caramelas, 

 Bayona, and all Galicia from the frontier of Portugal to Rivadeo 

 (Hidalgo 46). 



In Portugal P. lapillus is fairly abundant on the rocks of the 

 northern coast. In the west, it is common onlj' on the rocks of 

 Vianna do Castello, at the mouth of the River Liiuia in Miuho, and 



