372 PROCEEDINGS OF THE NATIONAL MUSEUM. vol.43. 



ORCHESTIA PLATENSIS Kr0yer. 



Cameron, Louisiana; L. K. Cary; 1 specimen. 



TALORCHESTIA LONGICORNIS (Say). 



Chandeleur Islands, Louisiana; L. R. Cary. 



Family AORIDiE. 

 JLEMBOPSIS, ne^A^ genus. 



Body slender. Side plates rather shallow, rounded. Antenna 

 2 about half as long as 1 ; accessor}' flagellum well developed. Lower 

 lip ^\dth mandibular processes strongly produced. Maxilla 1 with 

 inner plate small and bearing one apical seta; palp slender, second 

 segment with slender spines at tip. Maxillipeds with inner and outer 

 plates well developed, no teeth but many setae on inner plate; finger 

 of palp rather stout, exceeding preceding segment in length. Gnatho- 

 pod 1 in male: fifth and sixth segments stout, both armed on ventral 

 side with a strong spinous process; finger overlapping the palm. 

 Perseopods 3-5 with the second segment not very widely expanded ; 

 fourth longer than third, fifth much longer than fourth. L^ropod 

 3: rami subequal, much longer than peduncle. 



Tyjie of the genus. — Lemhopsis spinicarpus. 



LEMBOPSIS SPINICARPUS, new species. 



Rostrum small; sinus for first antenna deep, extending almost as 

 far as the posterior corner of the eye. Eyes rounded but with 

 antero-posterior axis slightly elongated. 



First antenna almost as long as body; first segment of peduncle 

 longer than head; antepenultimate segment one-fourth longer than 

 first; ultimate segment one-fourth as long as antepenultimate; 

 flagellum 23-25-segmented; accessory flagellum 7-segmented. Sec- 

 ond antenna reaching the tip of accessory flagellum of first; last two 

 segments of peduncle subequal in length; flagellum 10-segmented. 



Mandible with third segment of palp longer than second and 

 strongly ciliated on inner margin. Maxilla 1 : inner ])late with one 

 ])lumose seta; outer plate with eight spines: palp slender. Maxilli- 

 l)e(ls: inner and outer plates broad and well armed. Lower lips with 

 rather long mandibular processes. 



Gnathopod 1 of male: second segment devoid of long setae; fifth 

 segment slightly more than half as long as sixth, broad, thick; each 

 produced into a strong acute process on ventral margin; a deep 

 sinus between spinous process on sixth segment and palm, which is 

 straight; dactyl long, curved, finely denticulate on imier margin. 

 Gnathopod 2: fiftli and sixth segments oval and densely covered 



