NO. 3 HARTMAN : ORBINIIDAE, APISTOBRANCHIDAE, PARAONIDAE 321 



Aricidea uschakovi Zachs, 1925 

 Plate 43, fig. 5 



Aricidea uschakovi Zachs, 1925, pp. 1-3; Annenkova, 1937, p. 173. 



Aricidea antennata Annenkova, 1934, p. 658, figs. 2, 3. 



Aricidea longicornuta Berkeley and Berkeley, 1950, pp. 53-55, fig. 2; 



Berkeley and Berkeley, 1952, p. 38, figs. 68, 69. 

 Aricidea sp. Hartman, 1955, p. 170. 



Collections.— 1668-49 (1); 2117-52 (3); 2120-52 (20); 2152-52 

 (8) ; 2228-53 (1) ; 2232-53 (6) ; 2294-53 (1) ; 2311-53 (2) ; 2337-53 

 (1); 2445-53 (1); 2749-54 (6). 



This is characterized especially by the broad, truncate prostomium, 

 the long median prostomial antenna and the deeply bifurcated noto- 

 podial lobe of branchial segments. The first three segments are pre- 

 branchial ; they have well developed postsetal lobes in notopodia and 

 neuropodia; thereafter the neuropodial lobe diminishes in size. Branchiae 

 number 23 to 27 pairs; the more posterior ones have long and filiform 

 tips. 



The individuals listed under Collections, above, differ from the 

 original accounts indicated in the synonymy above, in that neuropodia 

 of posterior segments have setae of three instead of a single kind. These 

 setae are arranged in single transverse series. The uppermost 4 to 8 are 

 slender, long capillary setae; farther down are about as many thicker 

 ones terminating distally in a long straight arista ; these are followed 

 in the middle part of the fascicle by about 8 to 12 subuluncinate setae 

 in which the shaft is thicker, subdistally curved or sigmoid and the distal 

 end is slender; the 3 or 4 ventralmost setae are short, sigmoid, blunt 

 and uncinate (fig. 5). Unless looked for, these setae are easily over- 

 looked because they are largely embedded in the parapodial tissue and 

 pale yellow in color. Furthermore, preserved specimens often lack the 

 posterior end in which these setae occur. Except for these setae, the 

 specimens agree fully with accounts of Aricidea uschakovi Zachs as de- 

 fined by Annenkova, and with A. longicornuta Berkeley and Berkeley. 



Distribution. — Aricidea uschakovi was first described from Kola 

 Fjord, northern Russia, then recorded from the North Japan Sea in 115 

 to 230 meters (Annenkova, 1934 and 1937), western Canada in 75 to 

 230 fathoms (Berkeley and Berkeley, 1950) ; the present records are 

 from southern California in 12 to 293 fathoms. 



