NEPHTHYS C^CA. 11 



Mouth (Plate LVII, fig. 2) situated between a pair of crescentic fleshy lips, which at 

 their anterior attachment show a little fold or papilla — it may be sensory in function. 

 Posteriorly, at the mouth, the lips also have a free curve in front of the median 

 elevation indicating the proboscis. The latter in extrusion is a massive pinkish iridescent 

 organ shaped like a float or pear (Plate LVII, figs. 3 and 4), and scabrous from flat papillae, 

 especially towards its distal region, which has twenty-two longitudinal rows of them. 

 These increase in length distally, and each row has about five, or occasionally six papillae, 

 which in ordinary spirit-preparations have a tendency to be directed backward.. In some, 

 one or two small isolated papillae are scattered here and there on the region behind the 

 former. The median dorsal region has two rows which run forward to the peak at the 

 wide band which marks the dorsal angle of the aperture of the organ, and the terminal 

 papilla on the left or right is a little longer and more slender than the rest. On the 

 ventral surface a similar arrangement holds, one of the rows having an advanced 

 and somewhat longer papilla. From each row a band proceeds to the groove 

 between the terminal ridges of the lips, ten of these ridges being boldly marked 

 (Plate LVII, fig. 4), whilst a small median at each side completes the series. Each 

 ridge is separated from the adjoining ones at the margin of the lip and is continued a 

 short distance inward (in extrusion). From the outer side of the free tip arise two 

 flattened tapering papillae, the outer being somewhat longer. The dorsal and ventral 

 rows of the papillae diminish a little on each side of the middle line, the intermediate 

 one at each side, which is single, being the shortest. On slitting the proboscis a shelf 

 occurs inside the dorsal and ventral lips, then the smooth wall of the canal trends inward 

 for a short distance and breaks up into four prominent muscular ridges, with deep inter- 

 mediate grooves. One furrow therefore occurs opposite the middle of each lip, and 

 another at the intermediate line. At the distal end (in extrusion) of each central furrow 

 is a conical blackish horny tooth, the base having a visible spur directed to the left 

 (Plate LVII, fig. 5). The four muscular ridges, in all probability, can be protruded to 

 the tip of the organ, and thus the horny teeth will grasp the prey. When it penetrates 

 the sand uncovered by the tide it strikes the surface with the proboscis more frequently 

 than in Glycera, and is soon immersed. 



In some large examples the proboscis is deeply coloured with black pigment best 

 marked in the long papillae of the lips and distal rows, and which increases the iridescence 

 of the organ. 



In an example from Salthill, Co. Dublin, a hollow process projected from the base of 

 the extruded organ, the tip of the diverticulum being warty. 



Body. — Elongated (ranging to a foot or more in length), slightly tapered anteriorly, 

 and more distinctly so posteriorly, and with numerous segments, 140 — 150. Colour pearl- 

 grey with pinkish iridescence. This is but slightly marked in the middle line either 

 dorsally or ventrally, for a comparatively smooth surface of a fine pearly lustre occupies 

 those regions. The dorsum is convex, the ventral surface usually has a median groove, 

 which in front splits at the central prominence and runs forward on each side to terminate 

 at the mouth. The region in the fork is marked by a close series of longitudinal furrows, 

 which in extrusion of the proboscis are much stretched so as to reach from side to side. 



