NO. 4 SCHULTZ: ISOPODA 9 



Ilyarachna profunda, n, sp. 



(Plate 4) 



Diagnosis: Eyeless, pigmentless. No buccal mass visible from dorsal 

 view. Cephalon longer than and about as wide as first peraeonal seg- 

 ment. First peraeonal segment narrowest of all. Inconspicuous spines 

 on anterior edges of first four peraeonal segments. Small setae on lateral 

 margins of four anterior segments and also on anterolateral margin of 

 pleotelson. Peraeopods probably in general like those of co-generic spe- 

 cies, but only first ambulatory pair present on specimens examined. Pro- 

 podus and distal half of long carpus of first peraeopod with few short 

 spines. Proximal half of carpus, merus and basis with large spines. 

 First antenna with flagellum of approximately 28 articles ; second an- 

 tenna missing on specimens examined. Several plumose setae on first 

 antenna. Alaxilliped with four coupling hooks on endite ; palp with five 

 segments and large spines. Mandible with triarticulate palp ; incisor with 

 few teeth; and molar process with at least four large spines. Second 

 male pleopod with large copulatory organ with long recurved intrusive 

 process. Uropods missing. 



Measurements: Holotype male 3.0 mm long. Lengths of females to 

 3.8 mm. 



Type locality: 7047(1) ; La Jolla Canyon; 793 m; May 7, 1960; 

 green silty mud with sand. Lat. 32° 54' 21"N, Long. 117° 29' 53"W. 



Materials examined: 5639(2) ; 6820(1) ; 6832(1) ; 7047(1) ; 7949 



(1). 



Distribution: The species is found in the more southern canyons and 

 was taken between 461 and 1298 m. 



Affinities: The general appearance of the new species Is much like 

 that of Ilyarachna clypeata (Sars, 1899). Both species have a multiar- 

 ticulate first antennal flagellum of approximately 28 articles. It could 

 also be confused with /. acarina Menzies and Barnard (1959), but 

 lacks conspicuous spines on the anterior edges of the peraeonal seg- 

 ments. The male sexual appendage is long and recurved in the new spe- 

 cies, and is short and thick in I. acarina. 



JAEROPSIDAE 



Jaeropsis Koehler 



Jaeropsis concava, n. sp, 



(Plate 5) 

 Diagnosis: Lateral body outline concave, segment five narrowest. 

 Pigmentless except for small eyes of approximately seven ocelli. Small 



