CETTSTACEA. 517 



Mr. W. p. Cocks took some specimens in the trawl refuse, at 

 Gyllyngvase, Falmouth, and some specimens are in the Hopeian 

 Collection at Oxford, and labelled "South-west Coast of England." 

 It has also been taken in Scotland. 



Idotei appendiculata. — Rmo, Hist. Nat. de VEnt. Nereid, vol. v, 

 p. 107, 14,/. 29. 

 Not very common, it has been taken at Polperro. 



SPS^ROMID^. 



Genus, Sph^eroma. — Latrielle. 



Animal capable of rolling itself into a ball. Head small. 

 Eyes dorsally placed at the posterior angles. Antennae short. 

 Body wider than head. Posterior portion of the body (pleon) 

 united into one segment. 



Sph^roma sebratfm. — Falricius, Mant. Bist., \, p. 242. — Bate and 

 JFestwood, p. 405. 

 This species is common under stones and among pebbles on 

 all our coasts, from Kent to Cornwall, and in the Mediterranean. 

 We have also dredged fine specimens in Plymouth Sound, and 

 observed quantities in brackish streams in South Wales. 



Sph^roma RtTGiCAJSTDATA. — Leacli, Edin. Ency., vii, pp. 405-433. — 

 Bate and Westwood, p. 408. 



Prom the Hebrides to the coast of France has this animal been 

 obtained. In Cornwall we have found it at the mouth of the 

 river Tamar, 



This is a very active species, swimming, as all of the genus do, 

 with its back downwards, 



Spbueroma PEiDEAiJxiAisrAM. — Leach, Bid. Sci. Nat., xii, p. 345, 

 — Bate and Westwood, p. 455. 

 "Dr. Leach obtained this unique specimen from Mr. C. 

 Prideaux, who took it on the west coast of Devonshire" (prob- 

 ably Plymouth Sound). 



Genus, Dynamene. — Leach. 



Resembles a male Sphseroma, but is distinguished from it by 

 a notch in the tail. 



