6 Prof. M'Intosh's Notes from the 



posterior hooks have smaller (shorter) bases, and the posterior 

 outline is less curved toward the crown. 



The second species is Amphitrite figulus, Dalyell'^, not 

 uncommon in British waters as vvell as in more northern seas. 

 Its cephalic region differs from that of A. orrata in the 

 great developmeut of the fold in front of the tentacles, 

 which forms an arch over the mouth. At its outer edge, on 

 each side, it bends backward to become continuous with the 

 broad dark brownish fold behind the tentacles, which, how- 

 ever, in this form is limited in extent, for the median 

 portion is narrow. This structure of the posterior fold is 

 characteristic. The mass of grooved and frilled tentacles 

 springs from the hollow between these arches, and forms a 

 centre of very active functions during the life of the animal, 

 their colour then being pale orange or pink. The projecting 

 dorsal portion of tlie arch or lip is djirk brown iuferiorly. 

 Many cells and granules occur in their interior. Below 

 the dorsal arch is the mouth, and beneath is a globular 

 process followed by the lower lip, Avhlch is separated by 

 a groove on each side from the folds or arches. Behind 

 the lower lip ventrally is a well-marked collar with a 

 crenated anterior border stretching completely across the 

 ventral surface in the line of the first branchia. It has a 

 rounded free edge dorso- laterally, and a median and two 

 smaller crenations at its posterior border ; and these probably 

 usher in the change seen in the next ring, which has a distinct, 

 though small, median scute or pad. 



The body is 6-8 inches in length, enlarged in front and 

 taperirjg toward the posterior end, as usual in the family. 

 The segments number from ninety to a hundred, and of these 

 twenty-four bear bristles — the first being opposite the third 

 or last pair of branchiae. The dorsum anterioily is, in the 

 preparations, tessellated somewhat as in ScuUbregma, each 

 of the two lings in the segments being crossed antero- 

 posteriorly by folds which cut the ring into narrow spaces. 

 On the ventral side of the second branchia is a papilla, the 

 forerunner of the setigerous process which follows in the 

 next segment. Moreover, below each setigerous process is 

 a small papilla, as in A. cirrata, but these continue over 

 sixteen segments instead of the few in A. cirrata. The 

 bristle-tuft is situated at the posterior part of one ring, whilst 

 the following ring lies between the bristle-tufts. This 

 arrangement, however, extends only over thirteen or fourteen 

 rings, viz. from the interval between the second and third 

 * ^. 6r«w«e« of Stimpson r 



