120 Prof. M'Intosli's Notes from the 



to Mr. Arnold Watson for the opportunity of describing it 

 and for his notes and sketches of it Avhen alive. 



The annelid was found between tide-marks^ and when alive 

 was whitish or cream-coloured, but in sea-water with 2i per 

 cent, of formalin it passed through lemon-yellow to a dark 

 brown, the tinls being darker in some parts than in others, 

 whilst a few points remained cream-coloured. 



The head (PI. V. fig. 1) is somewhat conical, with a 

 smoothly rounded anterior iDorder, from the sides of which 

 spring the four subulate tentacles which taper distally and 

 are nearly equal in length. Behind these the snout is con- 

 stricted, then gradually widens till near the posterior border, 

 when a slight constriction again occurs, thus giving a 

 characteristic outline to the prostomium, the posterior border 

 of which is carried backward in the middle line. Just in 

 front of the central point is a minute boss, the presence of 

 which at once attracted Mr. Watson's attention, and which, 

 though in a diflerent position, simulates the unpaired 

 tentacle of Eulalia. On each side and a little in front of the 

 boss is a comparatively small eye, quite distinct at first, but 

 which gradually faded in the preservative fluid, as, indeed, 

 happens to other species of the genus. The peristomium bears 

 two tentacular cirri of similar shape to the tentacles and 

 scarcely longer. 



The body is about 3^ inches long and about ^^o of an inch 

 wide (Watson) in life, and it is flattened both dorsally and 

 ventrally, the latter surface being distinguished by a broad 

 median de})ressed band and a short lateral area in each 

 segment. On the dorsum, again, a similar effect is produced 

 by the slight elevations at the outer border of each 

 segment, though the median section is slightly convex 

 and of the colour formerly mentioned. It tapers a 

 little toward the snout, and much more gradually 

 toward the tail, which ends in two lobate or spathulate 

 cirri (PL V, fig. 2). The segments throughout are well- 

 marked, and in the preservative fluid (2^ per cent, formalin 

 in sea-water and then alcohol) a curious increase of the 

 pigment has occurred, with pale segment-junctions. The 

 dorsal and the ventral cirri are dark like the ventral surface, 

 but the setigerous processes remain pale; such of course, 

 though interesting, is the effect of the preservative fluid, and 

 must not be confounded with its original pallor. 



The feet form an even series along each side, the typical 

 foot (PI. V. fig. 3) having dorsally an ovate-rotundate 

 lamella, which varies a little in the posterior region — that is, 

 becomes more elongate and therefore more conical. The 



