388 LUMBRICONEREIS ACUTIFRONS. 



Head of the typical conical outline (Plate LXXII, fig. 5) with a slight median 

 inflection (backward) of the peristomial border posteriorly. The mouth has the concavity 

 of its posterior lip directed backward, and two rounded papillas lie in the fossa anteriorly. 



Body somewhat like that of L. bre wipes, the segments with the exception of the first 

 two being very narrow and the posterior lobe of the foot small. The specimen is 

 incomplete and most of the bristles are absent. 



Proboscis similarly armed to L. gracilis, the only apparent difference being the more 

 distinct shoulder at the posterior and outer border of the maxillas and the proportionally 

 broad and short posterior processes which have a boldly convex, almost semicircular 

 outer border. The great dental plates have fourth teeth, and in front of the two anterior 

 plates is a third granular bar on one side. An accessory granular horny belt also lies 

 to the exterior of the great plates. The mandibles unfortunately were lost. 



At the tenth foot (Plate LXXXII, fig. 7) the anterior border forms a blunt cone 

 beyond which the posterior lobe appears as an irregular flap. The bristles consist only 

 of one kind, viz., tapering, winged, translucent forms, but it has to be borne in mind that 

 the specimen had lost most of the bristles and hooks. The spines are pale. In some of 

 the feet of this form a small papilla appears above the foot, in profile, as in Plate LXXIV, 

 fig. 2. 



The general form of the elongated hooks from the middle of the body is shown in 

 Plate LXXXII, fig. 7 a. 



7. Lumbeiconereis acuhfrons, Mcintosh, 1903. Plate LXXXVII, fig. 7 — head; Plate 



LXXXVI, figs. 7-7 b— bristles. 



Specific Characters. — Head tapers to a delicate extremity from a base of the normal 

 breadth, and is rounded. Body little diminished anteriorly, and it remains of uniform 

 diameter throughout the fragment (f in.). Dental apparatus is translucent madder- 

 brown ; maxillse somewhat broad posteriorly, with a concave border, but taper in front to 

 strongly curved and sharp points. Their posterior appendages are constricted behind the 

 articulation, then expand into somewhat long processes with a straight inner and a convex 

 outer edge, the whole appendage being thus unusually long. The great dental plates 

 appear to have six strong recurved teeth, each of which is connected by a canal with a 

 brown band externally. A single plate with a tooth in front of these. Mandibles trans- 

 lucent, anchylosed in front, then split into the oblique cutting edge. 



Feet project evenly, and from above present a cylindrical setigerous process, behind 

 which is a short subulate papilla — sometimes probe-pointed — and largest in the anterior 

 region of the body. Dorsal bristles translucent and brittle, the tips russet-brown, 

 tapering distally to a fine point, in some considerably prolonged and winged. A few are 

 more slender, with a hair-like tip. Hooks translucent, with the shaft curved backward 

 distally and gradually dilating to the short neck. Main fang small, with several small teeth 

 on the crown above it. 



Synonym. 



1903. Lumbriconereu- acutifrons, Mcintosh. Ann. Nat. Hist., ser. 7, vol. xii, p. 146, pi. xii, f. 



29—32. 



