50 



Anomia striata, Heljiides 

 HippothjTis psittacea, North Sea 

 Terel)ratula cranmm, Zetland 

 Chiton Hanleji, North Sea, Hebrides 



,, raannoreus, „ „ 



Acmoea testudinalis, Irish Sea 

 Pylidium fiilvum, Clyde & S. of Ireland 

 Propylidium aneyloide, „ 

 Puncturella uoaohina, „ 

 Emarginula crassa, Cai'nan'onsliire 

 Trochus alabastrum, Orkney 

 ,, nndnlatus, Hebrides 

 „ heUeinus, Hebrides & Irish Sea 

 Scissurella crispata, Clyde 

 Aporrhais pes carbonis, Zetland 



Cerithium motula, Zetland 

 Scalaria Greenlandiea, North Sea 

 Chemnitzia rufescens, Clyde 

 Natica helicoides, Orkney & North Sea 



,, jiusilla, North Sea 

 Velutina tlexilis, „ 

 Trifliotropis borealis, South of Scotland 

 Fusus berniciensis, Noith Sea 



„ Norvegicus, „ 



„ Turtoni, „ 



Trophon clathratns, Irish Sea 



,, Bar\ieensis, North Sea 

 Mangelia Tre^-iUiana, „ 



„ nana, Orkney 



PhUine quadrata, North Sea 



The following are northern species, extending only to the British 

 Channel, or but little to the south of it. 



Xylophaga dorsalis 

 Mya truucata 

 ,, arenaria 

 Thracia viUosciuscula 

 CocModesma proetenue 

 Telliua pygmoea 

 Cyjirina Islandica 

 Astarte compressa 

 Modiola modiolus 

 Leda caudata 



Natica Montagni 

 Buecinum undatum 



,, Humphreysianum 



„ Dalei 

 Fusus Islandicus 



,, propinquus 



,, antiquus 

 Mangelia rufa 



,, turricula 



Megathyiis cisteUiila 

 Chiton ruber 

 Lacuna pallidiila 



,, %incta 



„ crassior 

 Rissoa Zetlandica 

 Skenia planorbis 

 Scalaria Trevilliana 

 Aclis nitidissuua 

 Eulima bihneata 



Crenella discors, I have never met with south of the British seas, and 

 suspect that when reported from the south of Europe, it has been con- 

 founded with Crenella marmorata, and Crenella costulata. Pliilippi's 

 description evidently applies to the former. 



The following find their southern limit in the neighbourhood of Vigo. 



Maetra solida Emarginula rosea ? Rissoa cingillus 



Pecten tigrinus ? Trochus tumidus Natica monilifera 



Crania anomaLi Lacuna puteolus Velutina lcE\'igata 



Chiton asellus Rissoa \-itrea Pui-piu-a lapillus 



canceUatus 



striata 



lAttorina Uttoralis, and Littorina rudis are met with in Lisbon. 



I refer to lists already given for northern species, which are to be 

 found in the Mediterranean, and the Canaries, most of which probably 

 do not extend far to the south of these districts. Ceratisolcn legumen, 

 Venus striatula, Patella pellucida, Acmwa virginea, and Trochus cine- 

 rarius ? appear to reach their extreme southward limit about Mogador. 



Proceeding from the south northward, we find the following species 



