CEtrSTACEA. 469 



not longer than tlie carapace; remaining- pairs compressed, a little 

 longer and more slender than the first. 



Bell says that he has given this name to the genus because it 

 was applied by Leach in MSS. in the British Museum, and 

 adopted by Bowdich in his ' ' Excursion in Madeira and Porto 

 Santo." 

 Plajstes lintteatta, — Leach MSS. — Floating Crab. 



This is a stray inhabitant of our shores, and drifted hither 

 after Atlantic gales. Its proper habitat is the Sargossa or Gulf- 

 weed of Mid- Atlantic. Sloane says that it was these crabs that 

 Columbus, finding alive on the Sargossa floating in the sea, con- 

 cluded himself not far from some land, in the first voyage he 

 made, on the discovery of the West Indies. 



In oar report to the British Association on the marine Fauna 

 and flora of S. Devon and Cornwall, Mr. Couch says, "In the 

 spring of the present year, 1867, an example of the Hawk's-bill 

 Turtle was taken in the channel, at not a great distance from the 

 French coast, and therefore not to be classed as British ; but 

 when brought alive and active into Polperro there were found, 

 adhering closely under the shelter of its tail, two full grown 

 examples of this crab ; the situation evidently chosen for support 

 and shelter ; for from the structure of their hind legs, it does not 

 appear probable that they can maintain themselves at the surface 

 without the aid of some extraneous support." 



Mr. Couch says " a species of the Genus Grapsus is in the 

 Athenseum at Plymouth,, under the name of G. Pelagicus, by Mr. 

 Prideaus, and known to Dr. Leach, but not in any published 

 work. It is understood that the collection in the Museum of that 

 Institution is confined to specimens taken on the borders of 

 Devon and Cornwall." 



LEUCOSIAD^. 



Genus, Ebalia. — Leach, Edwards, Bell. 



Carapace rhomboidal, angles rounded, antennae small, eyes 

 having short foot-stalks. 



This is the only British genus in this family. 

 Ebalia betehii — -'Bryer's Ebalia. — Leach, Malac Brit., p. 125 ; 

 Milne Edwards, Hist, des Crust., t. 2, p. 128. 



