43 



pilosus ? I have a specimen belonging to the variety 

 7, in which the teeth of the hinge are obsolete. 



LXII. Nucula, Lam. 

 1. margaritacea. 



Nucula margaritacea, La?«. — Nucula nucleus, 

 Turton. — Area nucleus, Lin. 

 Animal cream-white, the edges of the foot ciliated. 

 In cavities of dead bivalves, not uncommon. 



LXIII. Mytilus, Lin. 

 Subgenus Mytilus, Lam. 



Fam. Mytilacea. 



1. edulis, Lin. 



(3. Mytilus pellucidus, Penii. 

 Abundant on the rocky coasts. |(3. less frequent, 

 and not in general gregarious, as is the case with a. 

 The variety incurvatus probably exists on the Manx 

 coasts also. 



Subgenus Modiolus, Lam. 



2. vulgaris. 



Mytilus modiolus, Lin. — Modiola vulgaris, 



Flem. — Modiola papuana, Lam. — Modiola 



modiolus, Turt. — Test. jun. — Mytilus bar- 



batus, Lin. — Modiola barbata, Lam. — 



Mytilus curtus, Penn. 



Common in deep water on all the coasts. Animal 



figured by MuUer. The Modiola Tulipa of Lamarck 



has been confounded with this species by British 



authors. It is found on the south coast of England, 



and in the Frith of Forth. 



