22-11/80 (2 spec, USNM 75283), 28D-11/80 (6 spec, USNM 75284), 28F- 

 11/80 (1 spec, USNM 75285); MAFLA 2207K-11/77 (1 spec), 2210A-11/77 (1 

 spec), 2211F-11/77 (1 spec), 2422F-7/76 (1 spec), 2422-7/76 (1 spec, 

 USNM 55820), 2423B-7/76 (2 spec), 26401-11/77 (1 spec); STOCS HR-1 

 7/76 (3 spec, USNM 75214). 

 Supplementary Material: 



Flor ida--Hourglass Sta. BIV-1967, approx. 18 mi. W of Egmont Key, 

 27°37'N, 83°07'W (FSBC I 23526, 2 paratypes). 

 DESCRIPTION: 



Length, to 6.9 mm (previously reported to 3.2 mm); width, 0.2 mm. Body 

 small, thread-like, brown in color; complete specimens with up to 46 

 setigers. Prostomium oval, with four small eyes or two large conglomer- 

 ates of pigment spots near posterior border; with or without two addi- 

 tional eyespots near anterior border. Antennae minute, in a row between 

 eyes (Figure 30-28a). Palps long, completely fused d.irsally. Nuchal 

 organs as obscure, oval lobes behind eyes. Tentacular cirri minute; 

 dorsal cirri larger, ovoid, absent on setiger 2. Ventral cirri digiti- 

 form, shorter than parapodia except on far posterior setigers. Anal 

 cirri paired, long, cirriform. Superior simple seta blunt-tipped with 

 several lateral serrations (Figure 30-28b), present from setiger 1. 

 Composite spinigers with knobbed tips and coarse serrations (Figure 30- 

 28c), one per fascicle, absent posteriorly. Composite falcigers short- 

 bladed, with few coarse serrations (Figure 30-28d). Inferior simple 

 seta bidentate (Figure 30-28e), present on far posterior setigers. 

 Pharynx straight, brown, extending to setigers 4-7, with subterminal 

 dorsal tooth. Proventricle extending from setigers 4-8 to 6-9, with 19 

 (18-21) muscle cell rows. 



REMARKS: This species has been confused in the BLM-MAFLA samples with 

 Exogone verugera (Claparede, 1868). It differs from the latter princi- 

 pally in lacking dorsal cirri on setiger 2, and in having unidentate, 

 short-bladed composite falcigers. E_. atlantica in BLM-ST0CS collections 

 was identified as E_. gemmif era. 



PREVIOUSLY REPORTED HABITAT: 11-55 m; coarse calcareous sand; in scler- 

 actinian Siderastrea radians. 



GULF OF MEXICO BLM-OCS OCCURRENCE: Common in eastern and western Gulf 

 (Figure 30-27); 10-189 m; coarse to fine-very fine sand, silty fine to 

 very fine sand, clayey to sandy silt. 

 DISTRIBUTION: East coast of Florida, Gulf of Mexico. 



Exogone sp. A 

 Figures 30-29, 30a-e 



MATERIAL EXAMINED: 

 Gulf of Mexico BLM-OCS: 



MAFLA 2645D-2/78 (1 spec), 2645G-2/78 (1 spec, USNM 65673). 

 DESCRIPTION: 



Length, to 6.0 mm; width, 0.2 mm. Body small, slender; one complete 

 specimen with 43 setigers. Prostomium rectangular, with four small, 

 contiguous to confluent eyes in trapezoidal arrangement. Median antenna 

 extremely elongate, about twice as long as palps. Lateral antennae 

 about one fifth as long as median antenna (Figure 30-30a). Palps elon- 

 gate, completely fused dorsally. Tentacular, dorsal and ventral cirri 

 ovoid. Dorsal cirri present on all setigers. Anal cirri paired, long, 

 cirriform. Superior simple seta slender, aristate (Figure 30-30b), 



30-37 



