18 ALLAN HANCOCK PACIFIC EXPEDITIONS VOL.18 



Distribution: South Bay, Cedros Island, 16 to 19 fms; off Entrada 

 Point, Magdalena Bay, 28 to 34 fms; Gulf of California at Boca de 

 la Trinidad and San Marcos Island, 20 to 150 fms; Port Parker, Costa 

 Rica, 3 to 10 fms; off Santa Elena Bay, Ecuador, 8 to 10 fms. 



Ampelisca romigi, new species 

 Plates 10 and 11 



Description of female: Head not as long as first 3 body segments, 

 front margin broadly incised, lower front margin oblique, convex. 

 Upper pair of eyes behind upper edge of antenna 1, lower pair on front 

 oblique margin. 



Antenna 1 reaching beyond middle of article 5 of peduncle of an- 

 tenna 2, or longer than peduncle ; article 2 about one and one-half times 

 as long as 1 ; article 3 shorter than 1. 



Antenna 2 three fourths to longer than body; article 4 of peduncle 

 slightly longer than article 5. 



Mandible: spine row with 10 spines; palp article 3 about two 

 thirds as long as second article. 



Maxilla 1: outer plate armed with 11 spines; article 2 of palp 

 rather slender, apically armed with 4 spines, 4 cusp teeth, and 8 or 9 

 setae. 



Maxilliped: inner plate reaching beyond palp article 1, apex armed 

 with 2 chisel teeth ; outer plate reaching to end of palp article 2, inner 

 margin with 7 chisel teeth, rounded apex with 6 setal spines, the outer 

 3 plumose. 



Coxae 1 to 3 : lower posterior corner with a slit. 



Gnathopod 1 : article 6 three fourths as long as 5, palm convex, 

 lined with slightly pectinate setae; article 7 slightly more than half as 

 long as 6. 



Gnathopod 2 : article 6 slightly more than half as long as 5, article 

 7 two thirds as long as 6. 



Peraeopod 1 : article 7 slightly longer than articles 5 and 6 com- 

 bined ; anterodistal angle of article 4 slightly produced ; article 2 greatly 

 inflated. 



Peraeopod 2 : similar to 1 but with generic differences. 



Peraeopod 3 : posterior edge of article 5 with 2 or 3 sets of spines, 

 posterior edge of article 6 with 2 spines. 



Peraeopod 4: similar to 3 but with generic differences. 



Peraeopod 5 : lower edge of lobe of article 2 reaching joint between 

 articles 4 and 5, lower posterior edge oblique; article 4 with a posterior 



