A NEW TYPE OF AMPHIPODA. 119 



the insertions of the antennulse, but a real ' rostrum ' does not 

 exist. The angle between the antero-lateral and the lower lateral 

 margin is rounded off, and this lower margin is without any 

 protruding angle or process. The antero-lateral margin has at 

 the middle a small plate ivMcli is marTced off by a real articulation ; 

 this plate, which is freely projecting, and somewhat higher 

 than long, with the anterior margin curved, must be interpreted 

 as an eye-lobe, but visual elements could not be discovered. 



Antenmdce (fig. 2). — These are slightly longer than the head 

 and the two anterior thoracic segments. The peduncle measures 

 a little more than two-thirds of the whole antennula ; its basal 

 joint is rather robust and somewhat longer than the sum of 

 the two distal joints, which are subequal in length and con- 

 siderably more slender than the first; each of the two distal 

 joints with two subapical short hairs. The flagellum consists of 

 four joints, decreasing much in thickness from the second to the 

 fourth (fig. 3) ; the first joint is about as long as deep, the second 

 considerably longer, as long as the third, which, is slightly shorter 

 than the fourth ; the second and third joints each with two or 

 three subapical setsB ; the fourth joint with about seven apical 

 setae of various length. On the distal lower angle of the three 

 distal joints is found an olfactory seta (o.) ; the proximal seta is 

 as long as the terminal joint, and the two others a little shorter ; 

 all these setse are thick, with the end broadly obtuse and the 

 wall membranous. An accessory flagellum (fig. 3, a.) is developed, 

 originating from the inner and lower side of the end of the 

 peduncle, and reaching a little beyond the middle of the second 

 joint of the other flagellum ; it is three-jointed, the first and the 

 third joint short and subequal in length, the second somewhat 

 longer than both combined ; the two distal joints each with a 

 couple of short hairs. 



AntenncB (fig. 2). — These are a little shorter than the antennulse, 

 and as a whole somewhat more slender. The peduncle is slightly 

 more than twice as long as the flagellum; its three distal joints 

 decrease from the base in length and thickness ; the proximal 

 short joints without any projecting angle or spine ; the penul- 

 timate joint with a single seta on the lower side. The flagellum 

 is slender, decreases gradually in thickness, and consists of five 

 joints ; the four proximal joints are subequal in length, the fiftb 

 slightly longer ; each of the tw,o distal joints has a few short 

 apical setse. 



