LYSIANASSIDAE 



45 



lower corner concealed by side-plate 2. Side-plates 2-4 deep but not closely packed, 

 4 with moderately deep excavation; 5 notched, the two lobes subequal; 6 similar but 

 posterior lobe broader, though not deeper, than anterior; 7 trapezoidal, the hind margin 

 longer than the anterior. 



Pleon rounded, except for the rather high carina on segment 4, which slopes gradually 

 on the anterior side and falls abruptly and vertically on the posterior side, very much as 

 in Ambasia atlantica. Postero-inferior angles of segments 1 and 2 rounded, of 3 rather 

 less than a right angle, the corner rounded. Telson not twice as long as wide, cleft for 

 three-quarters of its length, lobes slightly dehiscent, apically acute with a subapical 

 spinule on outer side, and two lateral marginal spinules. 



Fig. 9. Ambasiopsis georgiensis, Brnrd. a. Side-plates 1 and 2 and gnathopod I, with palm further enlarged. 

 b. Gnathopod 2, with palm further enlarged, c. Profile of epistome and upper lip. d. Pleon segments 3 and 4. 

 e. Telson. /. Side-plates 4 and 5 and peraeopod 3. 



Antenna 1, peduncle stout, 1st joint apically produced on upper margin, 2nd and 3rd 

 joints very short, flagellum 8-jointed, 1st joint half as long as 1st peduncular joint, 

 setose, accessory flagellum 3-jointed, 1st joint the longest, but not as long as 1st flagellar 

 joint. Antenna 2, 4th joint longest, 5th shorter than 3rd, flagellum shorter than peduncle, 

 9-jointed. 



Epistome not projecting, upper lip produced in a rounded lobe. Mandible, cutting 

 edge straight with a denticle at each end, spine row minute, molar strong, truncate, 

 setose, palp longer than trunk, inserted over molar, 3rd joint two-thirds length of 2nd. 

 Maxilla 1, inner lobe short, ovate, tipped with two long and one short setae, outer lobe 

 with seven feebly serrate spines, palp extending beyond outer lobe, narrow, tipped with 

 two short stout spines and 1-2 setules. Maxilla 2, inner lobe distinctly shorter than 

 outer, as in faeroens is. Maxilliped, inner plate with 3-4 apical spinules, outer plate with 

 minutely serrate inner and distal margin but without spinule, palp rather stout. 



