I. '08. 



136 



Only a single specimen of Sahinea has so far been found 

 within the British area. It was dredged by Norman in 1861 

 in the neighbourhood of the Shetland Isles, and was recorded 

 by him as S. septemcarinata (Sabine). 



In a recent paper (1908), Hansen expressed the opinion that 

 the specimen is in reality an example of S. Sarsi, Smith, a 

 species which extends much further south than the Arctic S. 

 septemcarinata. Canon Norman presented his specimen to 

 the British Museum and there, through the kindness of Dr. 

 Caiman, I w^as able to examine it. The specimen, which is 

 unfortunately dry, is, as Hansen suggests, an example of 

 Sahinea Sarsi, Smith. 



Genus Crangon, Linnaeus. 



Steiracrangon, Kinahan, 1861. 



Rostrum depressed; carapace smooth, without longitudinal 

 dentate carinae. Eyes present. Lateral process of anten- 

 nules acutely pointed distally. First pair of pereiopods with- 

 out exopod ; second pair chelate, long and slender, reaching 

 to tips of first pair, dactylus less than half the length of pro- 

 podus, carpus considerably longer than ischium; dactylus of 

 fourth and fifth pairs not laminar. Endopods of last four 

 pairs of plcopods very much less than half the length of the 

 exopod, divided into two segments and without appendix in- 

 terna at base. Inferior apices of branchiae turned backwards. 

 Formula : — 





vn. 



vm. 



IX. 



X. 



XI. 



xn. 



XTTT. 



XIV. 



Podobranchiae, 



ep. 



ep. 



ep. 



... 



... 



... 



... 



... 



Arthrobranchiae,, 



... 



... 



1^ 



... 



... 



... 



... 



... 



Pleurobranchiae, 



... 





... 



1 



1 



1 



1 



1 



The two British and Irish species of Crangon may be thus 

 recognised : — 



I. Sixth abdominal somite dorsally smooth, C. vulgaris 



(p. 137). 



II. Sixth abdominal somite dorsally channelled 



and bicarinate, . . . C. Allmanni (p. 138). 



1 This arthrobranch is absent in C. antarcticus, Pfeffer, a species 

 which Caiman (1907) retains in the genus Crangon. Reliable informa- 

 tion as to the presence or absence of this gill in the other species of the 

 genus is necessary before a true estimate of the generic value of the 

 character can be formed. 



