MOLLUSCA. 63 



spun yam gives way, and the rope pulls the head of the 

 di-eg backwards, and disengages the teeth from the tangles 

 and stones. In transverse section the teeth form a trun- 

 cated ellipse round the central iron rod. 



The nomenclature adopted is that of Dr. Gwyn Jeffreys in 

 his valuable work on the British Mollusca ; and I am specially 

 indebted to him for his great courtesy in frequently aiding nie 

 in doubtful cases, and also carefully investigating shell-debris 

 containing minute species, which otherwise might have been 

 overlooked. 



Class CONCHIFERA. 

 Order Lamellibranchiata. 

 Fam. 1. Anomiidae, Gray. 

 Genus Anomia, L. 



Anomia epMppium, L. Jeffreys, Brit. Moll. ii. p 31 

 V. pi. 20. f. 1, 1 a-1 e. 



Not uncommon in the d6bris of the fishing-boats. 



Anomia patelliformis, L. Op.cit. ii. p.34, v. pi. 20. f. 2,2a-2c. 

 Common in the same region, as well as between tide-marks. 



Fam. 2. Ostreidae, Broderip. 



Genus Ostkea, L. 



Ostrea eduUs, L. Op. ciu ii. p. 38, v. pi. 21. 



Living examples are rare. The "rock" variety with 



purplish streaks, however, is occasionally found at the East 



Rocks on the under surface of stones in pools near low water. 



Fam. 3. Pectinida, Lamarck. 



Genus 1. Pectex, Pliny. 

 Pectenpusio, L. Op. cit. ii. p. 51, v. pi. 22. f. 1 & la. 

 Common j the living specimens come from the deep water 



