146 Mr. C, Spence Bate on British Edriophthalmous Crustacea. 



Genus 24. Niphargus (Schicidte). 

 I. N. Stygius (Westwood). 

 Deep well in Central England. 



Genus 25. Thersites (mihi). 



Upper antenna with second joint of peduncle produced from 

 the inferior side of the first. Second gnathopod terminating in 

 a brush. Telson double. 



1. T. Guilliamsoniana. Inferior antenna as long again as the 



superior. 

 "Weymouth, Prof. Williamson. 



2. T. pelagica. With the inferior antenna six times as long as 



the superior. 

 Moray Frith, Rev. G. Gordon. 



Subfamily VI. LEUCOTHOIDES. 



Carpus on both pairs of gnathopoda developed into a thumb 

 to the hand. 



Genus 26. Leucothoe (Leach). 



The process of the carpus on the first gnathopod as long as 

 the propodos. The hands of the second oval and larger than 

 those of the first. Telson single. 



1. L. articulosa (Mont.). Head furnished with a short down- 



curved rostrum. Lower antenna shorter than the upper. 

 Telson long and lanceolate. 

 Plymouth, C. S. B. Moray Frith, Rev. G. Gordon. 



2. L. procera (mihi). Hand of the first gnathopod short, of the 



second long, and narrower than in L. articulosa. The palm 

 denticulated. 

 Banff, Mr. Edwards. 



Subdivision II. DOMICOLA. 

 Being those of the normal Gammarina which live in abodes of 

 their own construction : some burrow in wood, some in clay ; 

 some erect tubes of mud, or stones and weed, and others build 

 nests with materials united by a substance secreted by the 

 animal. 



Family IIL Corophiidae. 



With the segments of the pleon not fused together. 



Section L Nidifica. 

 Comprising those which construct their own nests. 



