284 Syrrhoe, Pseudotiron 



as the basal part. Gnathopod 1, 5*^^ Joint fusiform, more than twice as 

 long as 6*^, bind margin densely fringed, 6*^ short. wideuing distally, bind 

 margin pectinate, palm slightly oblique, sinuous, setose, the palmar spine 

 with 7 or 8 denticles, linger reaching a little beyond the palm, Gnathopod 2, 

 3*^ Joint shorter than 4*^, 5*^ long, narrow, spinöse, more than twice as 

 long as 6*^, which is longer, and narrower than in gnathopod 1, scarcely 

 widened distally, ai-mature similar. Peraeopods 1 — 5 much as in S. crenulata 

 (p. 282), but 2'ijoint in peraeopods 3 — 5 less sti'ongly serrate. Pleopods, peduncles 

 with small interlocking process at apex, coupling spines large, 4 cleft spiues 

 on 1^* Joint of inner ramus. Teison not twice as long as broad. cleft a 

 little beyond middle, apices acute, with small lateral tooth above. L. 12 mm. 



Tropica! Atlantic (Virgin Island Culebra). Depth 713 mm. 



7. Gen. Pseudotiron Chevreux 



1895 Pseudotiron (Sp. un.: P. bouvieri), Chevreux in: Bull. Soc. zool. Frauce, 

 V. 20 p. 166. 



Body compressed, not indurated. Head triangulär (asin Synopia, p. 271)» 

 more advanced in d than in o . Side-plate 3 the largest, greatly excavate 

 (as in Syrrhoe, p. 281). Eyes (as in Argissa, p. 276) small. imperfectly deve- 

 loped. Anteuna 1 in d much shorter than antenna 2; accessory flagellum 

 3-jointed. Mouth-parts and gnathopods nearly as in Tiron (p. 275). Man- 

 dible normal, cutting edge and accessory plate dentate, spine-row of several 

 spines, prominent molar, but palp very slender, 3^ Joint scarcely longer than 

 broad. Maxiila 1, inner plate with several setae, outer with usual spines, 

 2* Joint of palp broad at apex. Maxilla 2, inner plate the broader with inner 

 margin partially fringed. Maxillipeds, inner plates normal, outer armed 

 with 3 long and 5 stout spine-teeth, palp rather long, finger long. Gnatho- 

 pods 1 and 2 long, slender, simple, setose. Peraeopods 1 and 2 short, 

 stout, finger short, hooked. Peraeopods 3—5, 2*^ Joint expanded, 6*^ very 

 Short, finger small, hooked. üropods 1 and 2, rami unequal; uropod 3, 

 peduncle short, rami long, broad, subequal, spinulose. Teison long, lanceolate, 

 cleft neai'ly to base. 



1 species. 



1. P. bouvieri Chevreux 1895 P. b., Chevreux in: Bull. Soc. zool. France, r. 20 

 p. 166 f. 1—14. 



Peraeon smooth. Pleon segments 1 — 3, bind margin denticulate, segment 4 

 with 3 denticles, segment 5 with 1 long tooth extending over segment 6. Side- 

 plate 1 distally expanded, 3*^ with straight front margin, liind part rectangular 

 below emargination, 4*^ much smaller, obliquely produced and rounded below a 

 slight emargination. Pleon segment 3, postero-lateral angle a little produced, 

 acute. Eyes in 9 , a group of 4 small lenses near front margin of head 

 (compare Argissa, p. 276), not observed in ö. Antenna 1 in o , 1^* Joint 

 rather longer than 3*^, 2*^ much shorter than either, flagellum a little longer 

 than peduncle, 9- or 10-jointed, accessory flagellum small. Antenna 1 in d,^ 

 1^* Joint much longer than 2^ and 3"^ combined, flagellum considerably 

 longer than peduncle, 1^* Joint much the longest, fringed, longer than the 

 3-jointed accessory flagellum. Antenna 2 in d, ultimate Joint of peduncle 

 shorter than penultimate, flagellum much longer, 23-jointed. Gnathopods 1 

 and 2, 3"^ and 4*'^ joints very short, 5* Joint long and slender, 6*^ linear, 



