Gutfy Marine Ldhoralorj/y S'f. Aiidn'io.t. 1.5 



hooks are accoin|)anic(l by the short bristh-s wiib tlie spjitu- 

 late tips. The posterior hooks ditler only in tlieir smaller 

 size and tiie brevity of the base. lu eoiu|)aring the hirger 

 with the smaller forms from Plymoutli, the essential characters 

 of tlie i)ristles and iiooks are as well shown by tlie smaller 

 as the larger. 



The tube is eoiuposed of a tougli internal lining, coated 

 with tine santl-gi'ains, the whole l)eing firm and resistent, 

 especially in the Canadian cxami)les. 



A form (BC), procured in numbers at Berehaven in 1886 

 by the Royal Irish Academy, apj)ears to be a variety of 

 P. tore/li, though presenting certain features of its own. 

 When the branehiai are absent the cephalic region presents 

 no deep fissure as in ordinai'y Sabellids, but the slight dorsal 

 furrow ends in a solid mass which, with an incurvation in 

 the middle, passes from side to side and then bounds the 

 region laterally to the ventral surface. This rim forms a 

 l)rojccting base to the branchiie. The collar commences as 

 a narrow process on each side of the dorsal fissure, slopes 

 obliquely forward and outward, and inclines laterally and 

 ventially into a deep though thin lamella, which attains its 

 mtiximnm in the mid-ventral line, where it is separated from 

 its fellows by a fissure. The branchiae preserve much of 

 their reddish-brown coloration in spirit, and they are of 

 considerable length. The {)igment is arranged on the pinnae 

 so as to make a series of circular bands, as in S. j^cniciUus 

 and other forms, thus conferring great beauty on the ex- 

 panded organs. In some cases, when mounted, the reddish- 

 l)ro«n pigment is in isolated masses at intervals along the 

 filament, and patches occur on the terminal process. There 

 are about eleven filaments on each side, sprniging from the 

 central region of the cephalic plate — a basal fissure, most 

 distinct ventrally, occurring dorsally and ventraliy. They 

 are eonneeied only at the base and are free throughout the 

 rest of their extent, and are long tapering organs with 

 proportionally short pinnae, which, as they reach the tip, 

 gradually diminish in length and end in a series of short 

 papilhe at the base of the terminal strap-shaped tapering 

 process. The chordoid skeleton is continued along the 

 centre of the flattened ti|) aiul into each pinna. In young 

 forms the jjinnie are short, but the flattened terminal strap 

 is well developed. The body is comparatively small, elon- 

 gated, and distinctly segmented from one end to the otiier — 

 a feature characteristic of the species. Fi!ty-six segments, 

 l)ut the tail in the majority of the examples was in jiroccss of 

 reproduction, so that the actual number of segnuiits must 



