HAIIDWICKE'S SCIENCE-GOSSIP. 



179 



crab, one of the Porcellanadce, or Porcelain-crab 

 family, and of the class Decapoda anomoura {vide 

 Science-Gossip, April, 1869, p. 74). The colour of 

 this Galathea is a greenish brown tinged with red : 

 there is a splendid species, G. strigosa, the " Spiny 

 Galathea," of a brilliant vermilion colour, the in- 

 tegument between the shell-plates being of a deep 

 cobalt-blue ; it inhabits deep water, but we once took 

 one off Bembridge Ledge. The " Spiny Lobster," 

 Palinurus vulgaris, is sold hereabouts under the 



crabs are scavengers) ; and the old familiar " Hermit 

 Crab," Pagurus Bemhardus. Nearly all of these have 

 been either figured or described in the past numbers 

 of Science-Gossip, and it is needless to dilate upon 

 them here ; but here are two strangers, not by any 

 means common, and we have got both the male and 

 female alive in one and the same haul : Corystes 

 Cassivelaunus, the "Masked Crab," the first pair 

 it has ever been our lot to capture. 



This genus is sometimes called "the Long-armed 



Fig. 98. The Male. 



The Masked Crab (Con/stes Cnssvidaunus). 

 Drawn from Nature, lite size. 



Fig. 93. The Female. 



name of the Crawfish ; it has no " pinchers," and 

 boils of a dull dirty red tinged with brown : the 

 real Crayfish, Astacus fluviatilis, belongs to a differ- 

 ent family altogether, and is armed with powerful 

 claws. 



Of the veritable short-tailed crustaceans we have 

 got " the Slender Spider-crab," Stenorhynchus tenui- 

 rostris ; " the Long-legged ditto," S. Phalangium ; 

 another crab, Pisa; the " Harbour Crab," Carcinus 

 mcenas ; the " Arched - fronted Swimming-crab," 

 Portunusarcuatus ; the " Cleanser ditto," P. Bepura- 

 tor, who has no special claim to this epithet (all 



Crab," a term that can only be correctly applied to 

 the male : it is of a pinky cream-colour and burrows 

 in the sand, leaving only the tips of its long seti- 

 gerous antennae visible. We are indebted to Mr. 

 Gosse for the discovery of the special functions per- 

 formed by these organs. "I have observed that, 

 when these crabs are kept in an aquarium, they are 

 fond of sitting bolt upright, the antennas placed 

 close together, and also pointing straight upward 

 from the head. This is, doubtless, the attitude in 

 which the animal sits in its burrow, for the tips of the 

 antenna? may often be seen just projecting from the 



