96 



DIVISION II. 



THE SESSILE-EYED CRUSTACEA. 



AMPHIPODA. 



This name was given by Lafcreille to this order, on account of 

 the animals comprised in it having two kinds of appendages, 

 one for perambulation, the other for swimming. 



ORCHESTIDM. 

 Gtentis, Talitrtjs. — Latr. 



First pair of antennae rudimentary, second long. First pair 

 of legs strong and simple in both sexes, second pair small and 

 feeble. 



Talitrtjs Loctjsta — Sand Hopper. — Linnceus. 



Abundant on sandy shores above high-water mark, mostly 

 under weed and offal. Dwelling in holes burrowed in the hot 

 sand. In the summer they are abundant, in the winter they 

 burrow into the sand. 



Genus, Orchestia. — Leach. 



Like Talitrus, but having the anterior two pairs of legs sub- 

 chelate. The second large and powerful in the male, but slender 

 and feeble in the female. 



Orchestia littorea. — Shore Hopper. — Montagu, Lin. Trans. Ix. 

 p, 9614,/. 4. 



Stony and pebbly beaches, above high- water mark. Tolerably 

 frequent on the shores of Plymouth Sound. 

 Orchestia mediierran"ea. — Costa, Rind dell accad. Set. nap, p. 

 171, 1853. 



This species has not yet been recorded from Cornwall, but it 

 reaches from the Mediteranean and the shores of the Crimea, 

 and the northern coast of Ireland, and also from W ales. I feel 



