226 Rev. T. Hincks on the 



quadvangularis." In some forms of S. Landshorovii the peri- 

 stome is much more elevated in the ovicelligeroug cells than 

 it is in the present, and forms a deep channelled sinus, at the 

 extremity of which the avicularium is placed. In this con- 

 dition the secondary orifice is subtriangular. 



There seems to be a large amount of variability in the 

 characters of the peristome as well as in the size and shape of 

 the zooecium itself*. The present form has the leading fea- 

 tures of the specific type, with a moderate amount of variation 

 in detail, and there hardly seems to be sufficient reason for 

 separating it from S. Landshorovii (PI. XIV. fig. 3). 



Bange. Spitzbergen, Hammerfest, Jan Mayen, Peninsula 

 of Kola, Nova Zembla, South Devon f- 



Subclass HOLOBRANCHIA, Lankester. 



Family Pedicellinidse, Hincks. 



Barentsia, Hincks. 



Barentsia major \, n. sp. (PI. XV. figs. 2.) 



Zoarium consisting of a rather stout, creeping, and branched 

 stolon, jointed at intervals, along which the pedicels sup- 

 porting the polypides are distributed ; pedicels of great length, 

 extremely slender below, expanding considerably towards the 

 summit, delicately ringed, of a very light horn-colour, rising 

 from a stout cylindrical base, conical above and of a whitish 

 colour, not annulated ; polypides large, white, expanding 

 from the base upward, slightly gibbous on one side, tentacles 

 numerous, the fleshy peduncle or stalk connecting them with 

 the pedicel comparatively long, enlarged immediately below 

 the base of the polypide. 



This species is allied to B. gracilis^ Sars, but is of very 

 much larger size. The pedicels for a great proportion of their 

 length are very slender, tubular, rigid, but towards the upper 

 extremity they widen out considerably and appear to be com- 



• See Hist. Brit. Mar, Pol. plate xlviii. figs. 6-9. 



t The South-Uevou specimen agrees very closely with Smitt's figiures 

 of his Escharella porifera (op. cit. plate xxiv. figs. 30, 31). 



X Busk has suhstituted, iu his ' Challenger ' Report (part 2, p. 40), the 

 MS. name Ascopodaria for Barentsia. As I am unable to recognize the 

 propriety or legality of this change, I have retained the latter, which wa3 

 the tirst published designation of this remarkable pedicelline group. I 

 hope to find an opportunity of discussing the grounds of this change on 

 some future occasion. 



