sandy shores from Massachusetts to Brazil ; 

 tn)i)ical West Africa: tropical Indian Ocean. 



Diopatra cuprea spiribranchis Augener, ll>()(i 



Dioputra spii-ll>ntiichis Augener, 1906: 145, pi. 

 5: Fig. 88-96. -Nonato and Luna, 1970b: 74. 



D( so-iptidH. — Length up to 260 mm. Tube 

 muddy, fragile, without shell fragments. Body 

 pale with two brown bars close together on 

 posterior margins of branchiferous segments. 

 Ceratophores of occipital antennae with about 

 10 rings. Pseudocompound hooks of first three 

 feet strongly bidentate or even tridentate with 

 a slender third tooth. Comb-setae with 20-25 

 teeth. Ventral cii-ri cirriform on first four feet. 



R( Diark:^. — This subspecies re.sembles D. iica- 

 ti-l(lviis Hartman in having pseudocomjjound 

 hooks with the third tooth slender and in having 

 comb-setae with numerous fine teeth, but the 

 ])igment pattern is quite different and so is the 

 nature of the tube. 



Records. — Ten small specimens in 40-160 m 

 off Beaufort (21, *). 



Dixtrihiilidii. — ^West Indies and Brazil in 21- 

 200 m on muddy sand. 



Rhamphobrachiiim atlanticiim. New Species 



Fisrure 8a-h 



Holoti/pi. — USNM 43124: one paratype, 

 USNM 43125. 



Dcscriptidii. — Both type specimens incom- 

 plete: holotype 55 mm long for 85 .segments and 

 possibly 120 mm long when complete. Tube 

 constructed of mud and mucus with large shell 

 fragments jilastered over anterior end. Anterior 

 end of body rounded (Figure 8a) but middle 

 segments flattened dorsally and 7 mm wide. 

 Color flesh brown, tentacles speckled, and 

 head flecked with dark pigment. 



Occipital tentacles with short, 5-ringed cera- 

 tophores and rather long tapered ceratostyles. 

 Frontal tentacles ovoid and swollen. Tentacular 

 cirri dorsolateral and well developed. Mandibles 

 with well-developed cutting edges and pale 

 straight shafts. Ma.xillae rather soft and brown; 

 Mx. I = 1: Mx. II = 8-HO; Mx. Ill = 9-hO; 

 Mx. IV = 8-^9: Mx. V = 1-^1. 



First three feet obviously capable of great 

 extension but retracted and wrinkled on holo- 

 type. Setae retracted but dissection revealed 

 very long setasacs extending back to segment 

 45. thirst three feet with well-developed dorsal 

 and ventral cirri (Figure 8b), but both cirri 

 reduced on subsequent segments. First gill as a 

 single filament on dorsal cirrus of sixth foot 

 but subsequent gills with a maximum of six 

 pinnately arranged filaments (Figure 8c). Ven- 

 tral cirri all cii'riform to fifth foot but thereafter 

 as glandular' cushions below setigerous lobes. 

 Setigerous lobes with a low presetal lip and a 

 conical postsetal lobe for first three feet. Post- 

 setal lobe I'educed on fourth to tenth foot and 

 represented by a low postsetal boss on subse- 

 quent feet. 



First three feet with three setal types: (a) six 

 to eight fine, pointed acicula extending into 

 base of dorsal cirrus: (b) about four stout, 

 greatly elongated acicula with curved tips (Fig- 

 ure 8f): and (c) about four much finer setae with 

 two rows of spines along the shaft and hooked 

 tips (Figure 8g). Setae of posterior feet include 

 three or four pointed acicula and numerous 

 winged capillaries (Figure 8e). Bidentate acicu- 

 lar setae (Figure 8h) and fine comb-setae with 

 15-20 teeth (Figure 8d) from about setiger 25- 

 30. No spinigerous compound setae present. 



Re marks. — The length of the curved acicula 

 and spiny-shafted hooks of the first three feet 

 is remarkable. When these feet with their everted 

 setae are fully extended they must reach far 

 beyond the head and provide an efficient 

 means of grasping prey. The hooks in other 

 species of the genus are sometimes compound 

 but here they appear plain and the tips lack 

 sheaths. 



Two species of Rlia iiiphobrachiuni have been 

 recorded from the United States, namely R. 

 «f/((.s.s-/,:/ Ehlers from Florida to South America 

 in 770-805 m and R. hnigosetasn ni E. and C. 

 Berkeley from Califoi-nia to the Pacific coast 

 of Mexico in 18-740 m. R. loiigosctdsum is im- 

 mediately distinguished from R. atlanticum by 

 the possession of spinigerous compound setae 

 in 5th to the 15th foot and branchiae from the 

 8th to 9th foot. R. agassizi (and R. cluoii Ehlers 

 (1908) from the Indian Ocean) are closer since 

 they too lack spinigerous compound setae, but 

 again the gills start farther back. In R. agassizi 

 the first gill appears on the 11th to 17th foot 



55 



