CKUSTACEA. 405 



GAMMARUS LORICATUS (Sabine). 



.,iinrits loricntus, Sabine, Parry's Voyage, Append., p. ccxxxi. t. i. 

 f. 7. Kroyer, 1. c., p. 22. t. i. f. 4 ; Edw., 1. c., p. 52. 



GAMMARUS BOREUS (Sabine). 



Gammarus boreus, Sabine, 1. c., p. ccxxix. 



? Sqidlla pnlex, Degeer, Ins. vii. p. 525. t. xxxiii. f. 1, 2. 



For an excellent description of this species, and a critical 

 examination of its identity with Squilla Pulex of Degeer, I 

 must refer to the original account of it by Colonel Sabine, 

 above quoted. 



GAMMARUS KROYERI (n.s.). 

 PLATE XXXIV., fig. 4. 



Antennis superioribus inferioribus dimidio longioribus, abdominis seg- 

 mentis quatuor anterioribus in medio, secundo et tertio ad angulum 

 inferiorem posticum, in dente productis. 



Superior antennae half as long again as the inferior ; the 

 accessory filament extremely minute ; the anterior (four) tho- 

 racic epimeral plates increasing gradually in size, rounded be- 

 neath, the fourth slightly produced at the posterior margin ; 

 the fifth and sixth with a lobe at the anterior-inferior portion ; 

 the seventh oval. First and second pairs of thoracic feet che- 

 liform ; the second with the penultimate joint very broad, ob- 

 liquely truncate ; third and fourth simple ; the three following 

 with the third joint very large and oval. Abdominal false feet 

 normal. There is a small triangular dentiform process, di- 

 rected backwards, on the middle of the posterior margin of 

 the anterior four segments of the abdomen, and the postero- 

 inferior angle of the second and third is similarly produced. 



This species has a very close resemblance to Amphitoe bi- 

 cuspis of Kroyer. It is however a true Gammarus, as the ac- 

 cessory filament of the superior antennae does exist, although 

 extremely small. 



Hub. Wellington Channel, in thirty-five fathoms. 



