LYSIANASSIDAE 



33 



The present specimen is larger than either the ' Challenger ' or the ' Scotia ' specimens. 

 The strongly chitinized apices of the outer plates of the maxilliped are very noticeable. 



Distribution. Marion Island 90-135 m.; Cape Virgins 100 m.; Gough Island 100 

 fathoms; Falkland Islands; Kerguelen. 



Genus Stomacontion, Stebb. 



Stebbing, 1906, p. 16. 

 Barnard, 1916, p. 109. 



The species described below is provisionally placed in this genus, though differing 

 in certain respects. In other respects it combines the characters of both Acontiostoma 

 and Stomacontion. From both it differs noticeably in the 1st gnathopod. 



Chilton (1912) was of opinion that Stomacontion was not generically distinct from 

 Acontiostoma, and in describing S. capense I was of the same opinion. But further study 



b. ^^ c. £ 



Fig. 4. Stomacontion insigne, n.sp. a. Gnathopod 1 . b. Gnathopod 2. c. Maxilla 1 . d. Maxilla 2. 

 e. Peraeopod 2. /. Peraeopod 3. g. Pleon segments 3-6 and uropods. h. Telson. 



of these forms is necessary. If the palp of maxilla 1 is of generic importance the 1st 

 gnathopod might also be considered as such. 



Stomacontion insigne, n.sp. (Fig. 4). 



Occurrence: St. 160. Shag Rocks. 1 specimen about 6 mm. 



Description. Integument (as preserved) moderately indurated, smooth. Eyes 

 absent. Side-plates deep, non-setose, 1st subtriangular but not markedly shorter than 

 2, 4 somewhat truncate below, 5 with posterior lobe deeper than anterior. Pleon seg- 

 ment 3 remarkably shortened dorsally, forming a rounded hump, postero-lateral angle 

 quadrate, slightly produced; segment 4 falling away abruptly from segment 3, with a 

 strong upturned process on posterior margin. Telson oblong, slightly longer than 

 broad, apex angularly and shallowly excised. 



Antenna 1 stout, 2nd and 3rd joints very short, flagellum 4-jointed, 1st joint longest, 

 accessory flagellum2-jointed, 1st joint slender, longer than 1st joint of flagellum, 2nd joint 

 minute. Antenna 2, 5th joint shorter than 4th, flagellum subequal to 5th joint, 4-jointed. 



