35 



Genus Cyclostrema. 



C. depressum. 



Helix depressa, Mont. 



On the rocks at low water mark ; abundant. 



Genus Phasianella, Lam. 



P. Pullus, Lam. 



On fuci at low water mark ; not common. 



Genus Trochus, Auct. 



T. Ziziphinus, Auct ; & var. (Isevis.) 



Under stones at low water mark ; and by dredging ; common. 

 T. elegans, (N.S.) C^'. ^//^^^'^,r^>rr^---^ 



In deep water; common. 

 T. Montacuti, (N.S.) 



With the last ; rare. 

 T. cinerarius, Auct. Brit, and var. (intermedia.) 



Under stones and among fuci at low water mark : common. 



The variety (of which I only found one specimen by dredging in deep 

 water,) seems to connect this species with the following. 

 T. umbilicatus, Auct. Brit. 



With the preceding ; common. 

 T. tumidus, Mont. 



In deep water ; common . 

 T. Magus, Auct. 



With the last ; rare. 



Genus Lacuna, Turton, 



L. quadrifasciata, Turt. 



On fuci at low water mark ; not common. 

 L. pallidula, Turt. 



With the last ; not common. 



