150 Mr. C. Spence Bate on British Edriophthalmous Crustacea. 



Division 11. Hyperina. 

 Family V. Hyperidae. 

 Pleon not folded beneath the pereion. Antennae well developed 

 and exposed. Pereiopoda not prehensile. 



Genus 1. Hyperia (Latreille). 

 Head large. Antennse short. Gnathopoda scarcely prehensile. 

 Telson lanceolate. 



1. H. Galba (Montagu). 

 Hyperia Latreillei (Edwards). 



The first six or seven articulations of the filament of upper and 

 lower antennse fused. Upper antenna longer than the lower. 

 Pereiopoda short. 



2. H. oblivia (Edwards). Lower antenna longer than the upper, 



and the segment of the filament of the upper antenna only 

 fused. Pereiopoda long. 

 Moray Frith, Rev. G. Gordon. 



Family VI. Phronomidse. 

 Some of the pereiopoda prehensile. 



Genus 1. Phronoma (Latreille). 

 The first of the posterior pereiopoda cheliform. 



1. P. sedentaria (Latr.). Antennse short. Feet of first two pairs 

 compressed. The two fingers which terminate the fifth pair 

 of legs are large, curved, and armed with a tooth on the 

 internal border. 

 Shetland, Dr. Fleming [White's Cat. of the British Crustacea). 



Family VII. Typhidse. 



Antennse not exposed. Pleon compressed beneath the pereion. 

 The squamiform process of the posterior pereiopoda largely deve- 

 loped, and acting the part of an operculum. 



Genus 1. Typhis (Risso). 

 1. T. nolens (Johnston) [White's Cat. of the British Crustacea). 



Group B. Aberrantia. 

 Family VIII. Dyopedidse. 

 The last segment of the pereion and the last of the pleon 

 absent. Coxse of last two pereiopoda fused with the body of the 

 animal. 



Genus 1. Dyopedos (mihi). 



The sixth and seventh pairs of legs attached to the sixth seg- 

 ment of the pereion. The last pair oi pleopoda absent. Telson 

 single. 



