Mr. C. SpenceBate on British Edriophthalmous Crustacea. 141 



rudimentary. Gnathopoda generally prehensile. Last pair of 

 posterior pleopoda terminating in two stylets which are more 

 or less fringed with cilia. 



Genus 11. Darwinia (mihi). 



Pereion inflated. Upper antenna without secondary appendage. 

 All the feet terminating in simple hooks, not subcheliform. 



1. D. compressa (mihi). Head produced into a rostrum. Posterior 

 pleon slender and weak, lying compressed beneath the body 

 of the animal. Upper antenna stouter and longer than in- 

 ferior. Telson single, lanceolate. 

 Banjff, Mr. Edwards, Macduff, Mr. Gregor, 



Genus 12. Iphimedia (Rathke). 

 Not compressed. Upper antenna without secondary appendage. 

 Telson simple. First gnathopod simple ; second subcheliform. 



1, /. ohesa (Rathke). Head produced into a rostrum. Upper 



antenna as long as the lower. The last segment of the 



pereion and all the segments of the anterior pleon armed 



on the dorsal ridge with two parallel spines. 



Tenby, W. Webster j Esq, Macduff, Mr. Gregor, Plymouth, 



CS.B. 



Genus 13. Acanthonotus (Owen). 



First gnathopod subcheliform. Telson divided. Mandible 

 palpigerous. 



1. A, Owenii (mihi). Head armed with a rostrum. Four an- 

 terior segments of the pleon produced on the dorsal surface 

 posteriorly into a strong spine, the posterior margins also 

 denticulated laterally. Anterior coxse produced each to a 

 point, the fifth directed posteriorly. 

 Banff, Mr, Edwards, Macduff, Mr, Gregor. 



Genus 14. Dexamine (Leach). 

 Upper antenna with the third articulation of the peduncle 

 reduced in length to that of the filament. Mandible non- 

 palpigerous. Telson divided. 



1. D. s/?moM (Montagu). Head with a short rostrum. Upper 



antenna with the second articulation longer than the first. 



Four anterior rings of pleon produced dorsally into a spine 



posteriorly. 



S. Devon [Montagu, Brit. Mus. Coll.), Linn. Trans, vol. xi. 



Plymouth, C. S. B. Penzance, — Harris, Esq., TV, Webster, Esq. 



Macduff, Mr. Gregor. 



