6 Rev. T. Hincks on the 



Bugiila Murrayana (normal), Jolmston. 



Houston Stewart Channel, in shell; Virago Sound. [Van- 

 couver Island [Dawsoii) ; Britain (chiefly north), Scandinavia, 

 Spitzbergen, Barents Sea, Greenland, Labrador, Gulf of St. 

 Lawrence, New England.] 



Family Cellariidse. 



Cellaeia, Lamouroux (part.). 



Cellaria horealts^ Busk. 



Virago Sound. Off Cumshewa Harbour ; Houston Stew- 

 art Channel. Abundant and very fine. [West Greenland, 

 6-10 fms.] 



The internodes in this fine and characteristic species ex- 

 pand regularly from the base upward, and are often of very 

 considerable width above. The specimens from the Queen 

 Charlotte Islands are in some cases very large, attaining a 

 height of more than 2^ inches. 



Cellaria mandibulata^ n. sp. 



Zoarium slender, irregularly branched ; the internodes at- 

 tenuated at the base, joints black, Zooecia contiguous in the 

 same line, bluntly pointed or rounded above, the margin 

 trending outwards to about the middle, and from this point 

 slanting inwards to the base, truncate below (lozenge-shaped) j 

 area slightly depressed, smooth, margin distinct, subcrenu- 

 late ; orifice semicircular, situated in the upper third of the 

 area, lower lip arched. Avicularian cells in the line of the 

 ordinary zooecia, which they resemble, but are shorter and 

 very much broader (about twice the width), prominent 

 above, almost the whole of the upper portion (more than a 

 third of the length) occupied by a semicircular orifice, which 

 is filled in by a stout mandibular plate of a very dark horn- 

 colour, the edge black. Ooecial opening at the very top of 

 the cell, and of much the same shape as the orifice. 



Loc. Houston Stewart Channel ; Virago Sound. 



C. mandihulata bears a close resemblance in most respects 

 to C. Jistulosa, and is separated from it on the strength of the 

 very marked difierences in the avicularium, which is found 

 to be the best criterion for distinguishing specific forms in 

 this genus. The avicularium of the latter is (morphologically) 

 a dwarfed cell, with the oral valve slightly modified. In the 

 present species the avicularian cell is in some respects larger 

 than the ordinary zooecium, from which it is distinguished 

 chiefly by its great breadth, its prominence, and its ample, 



