Gaily Marine Laboratory , St. Andrews. 23 



Pi.s/d cretucca, (jruhc, the tucll'tli .species, is readily 

 distinguished, amonj^st other characters, by the peculiar 

 liunip on the ])Ostc:rior outline of the liook just .ihove the 

 hase. It conies from the south-^yest of Ireland and other 

 regions in deep water, 



The Ilebridcan rxani|)le o( Scione ninculata, Dalycll (?J, the 

 tliirteenth form, has the cephalic region so injured that all 

 that can at present be said about it is that it appears to 

 correspond with that of allied Terebellids. 



Body apparently about 2}j to 3 inches iu length, and of 

 the ty[)ieal outliue. In s[)irit it had at first a red;lisii-bro\vu 

 a()pearance, and was everywhere sj)ecUled with white, with 

 the exception of the ventral scutes. 



The number of the pale golden bristlc^bundles is unknown. 

 The shafts are nearly cylindrical till near the end, where 

 they are slightly narrowed below the wings. The tip is 

 gently tajjcred to a fine extremity, and furnished with a 

 narrow wing on each side. 



The hooks are distinguished by the straightness of the 

 posterior border and by the presence of only a single tooth 

 above the large fang, which stands nearly at a right angle 

 to the posterior outline. The anterior outline below the 

 great fang is not elongated, and has the process for the 

 ligament about its mid lie, the edge be3'0Md it having a 

 slight incurvation. The basal regiou is deep and com- 

 paratively short in contrast with that of Terebella nebulosa, 

 another form having only a single tooth above the great 

 fang. The inferior outline is convex, with a slight sinuosity 

 at either end. On the whole, the general outline of the hook 

 approaches that of F'istd cristata, while materially differing 

 iu detail. 



The southern Leprma lapidaria, L,, the fourteenth species, 

 has oa the cephalic plate a well-marked dorsal rim, which 

 curves laterally to become continuous with the highly-arched 

 supra-oral fold, often thin anteriorly. It beai's numerous 

 slightly-grooved tentacles, which also differ from those of 

 many other forms in adhering after preparation. They are 

 pale yellow in life, with the red blood-vessel in the centre. 

 The buccal process or "tongue" inferiorly often projects as 

 a smoothly-rounded mass obscuring the rim of the segment 

 bcliind it. The structure of the cephalic regiou of this 

 inhaliitant of fissures in rocks does not differ materially 

 from those which dwell in tubas, except that the lingual 

 process or boss is large and that the tentueles show only 

 a slight groove at the base, and it seems to disap[)ear froiu 



