480 Stimpson on the Crustacea and Echinodermata 
islands, belongs to this division. They live under flat 
stones, from half-tide to low-water mark, and represent the 
Porcellane of warmer latitudes. 
DERMATURUS MANDTII. Brandt. 
Dermaturus Mandtii, Branpt; Mélanges Biologiques, i. 57. 
Hab. Island of St. Paul. 
Mus. Acad. Petrop. 
HAPALOGASTER MERTENSII. Brandt. 
Hapalogaster Mertensii, BRANDT; Mélanges Biologiques, i. 58. 
Hab. Sitka, (Wosnessenski.) 
Mus. Acad. Petrop. 
Trine PORCELLANIDEA. 
PORCELLANA EDWARDSII. De Saussure. 
Porcellana Edwardsii. De Saussure ; Rev. et Mag. de Zool. v. 366. Pl. XI. f. 3. 
Carapax strigose; surface of hands scabrous ; anterior 
margin of carpus in the first pair of feet, and of the third | 
article in the remaining pairs, BOREAS toothed. 
Hab. Mazatlan, (Verreaux.) 
Mus. Paris. 
PORCELLANA RUPICOLA. Stimpson. 
Plate XIX. f. 2. 
Porcellana rupicola, Stimpson; Proc. Bost. Soc. Nat. His. vi. 85. 
Carapax moderately depressed ; front triangular, consid- 
erably deflected, with a blunt extremity, and a notch e 
groove at the base separating it from the orbit. Surface 0 
the feet and anterior half of the carapax scarcely met 
with granules but slightly prominent. The portion of 
- 
