HYALINCECIA SICULA. 417 



At the twentieth foot the dorsal cirrus is still the same. Behind the dorsal bristles 

 is a minute flat papilla, the remnant of the longer process anteriorly. The translucent 

 dorsal bristles are considerably longer with traces of wings at their finely tapered tips 

 (Plate LXXXIV, fig. 6 a). Below are two strong bifid hooks (Plate LXXXIV, fig. 6b), 

 the inferior hook marking off the setigerous region from the long elevated ventral pad 

 formed by the metamorphosed ventral cirrus. 



The species secretes a thin but tough tube (Plate LXIV, fig. 3 b) which is coated 

 with the greyish sticky mud amongst which it dwells. 



This form approaches the Diopatra (Paradiopatra) fragosa of Ehlers in the absence 

 of branchiae, and in the aspect of the head, tentacles, and body. The armature of the 

 proboscis is also similar. Ehlers 1 describes and figures the tube, however, as formed 

 of fragments of shells set on edge after the manner of tubes of Owenia filiformis. 



Genus LXIX. — Hyalincecja, Malmgren, 1867. 



Head with ovate frontal lobes, five smooth filiform tentacles arising from ringed 

 cirrophores. Eyes two, or absent in the preparations. Palpi in the form of two bulbous 

 pads, separated by a median fissure ventrally. No tentacular cirri. Body long, flattened, 

 slightly tapered anteriorly, more distinctly tapered posteriorly, and ending in two long 

 anal cirri, with the anus on the dorsum of the last segment (pygidium). Proboscis with 

 maxillge enlarged posteriorly, and all the parts well developed. Mandibles have long 

 tapering shafts and leaf -like notched anterior edges. First foot is large and slopes forward, 

 and has a disc-like process at the tip. It carries falcate bristles. Ventral cirrus soon 

 becomes pad-like. Winged and brush- shaped bristles occur dorsally in the anterior feet, 

 then strong bifid hooks appear below them with a few winged bristles inferiorly. 



1. Hyalinoecia sicula, Be Quatrefages, 1865. Plate LXIV, figs. 4-4 c — head, teeth, and 

 tube; Plate LXXV, fig. 10— foot; Plate LXXXIV, figs. 7-7 d— bristles. 



Specific Characters. — Head as in Hyalinoecia tubicola. The small black eyes lie 

 outside the base of the long lateral tentacles. All the tentacles have ringed cirrophores. 

 Body characterized in spirit by two parallel bands of brown from a transverse belt behind 

 the head, and by a brown spot between each foot from the fifth backward. Maxillas 

 strongly curved and sharp-pointed ; the posterior appendages elongated and conical. The 

 right great dental plate has nine or ten teeth ; the left has eight ; the azygos plate has 

 eight. The curved anterior plates seem to have few teeth — four or five on the right, 

 fewer on the left. Mandibles with long, narrow, and tapering shafts, and a blunt, leaf-like 

 anterior plate with a few notches. Branchiae commence on the fifth foot, and extend as 

 a simple process beyond the fiftieth foot. The bristles of the anterior feet {e.g., the first) 

 have the end of the shaft slightly dilated, and the bevelled region has spikes. The 

 moderately elongated terminal piece is sloped at the base and bifid at the tip, the 



i < Florida Annel./ p. 76, Taf . xxi ; f . 4. 



110 



