90 BICELLARIID^E. 



red colour when dry. Zooecia biserial, much elongated, 

 attenuated below ; aperture extending almost to the 

 bottom of the cell, wide above, almost pointed below, 

 with a stout cylindrical spine, jointed at the base, on the 

 upper and outer angle, and a denticle in front of it. 

 Avicularia placed about halfway down the cell, large, 

 elongate, the head not much arched, the beak curved 

 for about a third of the length, with a very short hook at 

 the extremity. Ooscia extremely shallow, hemispherical, 

 as viewed sideways, the aperture occupying almost the 

 whole of the front. 



HABITAT. In the Laminarian region, and 6n shells, &c., 

 from deep water. 



LOCALITIES. Cullercoats, common (Coppin) : south 

 coast of Durham, extremely abundant (J. Hogg) : Scot- 

 land (Dalyell) : Shetland, 5-7 miles east of Balta, 40-50 

 fins., scarce (A. M. N.) : Seaham Harbour (G. Hodge) : 

 Scarborough (Bean) : St. Andrews, Coralline ground, 

 attached to shells, abundant (Dr. M'Intosh) : Loch Ryan, 

 oyster-shells (Landsb.) : Filey, Yorkshire; Menai Straits 

 (T. H.) : Wick, abundant ; Peterhead, rare (C. W. P.) : 

 Clontarf (Trin. Coll. coUect.) . 



GEOGRAPHICAL DISTRIBUTION. Christiansund and Bejan, 

 40-60 fms. ; Lofoten (M. Sars) : Bahusia and Norway, 

 common, 30-130 fms. (Smitt) : St. George's Banks, 110 

 and 150 fms. (Smith and Harger). 



This species had been confounded with B. plumosa until 

 Mr. Alder pointed out, with his accustomed accuracy and 

 clearness, the characters which separate them. 



B.fastigiata is of stouter and stiffer habit, and much 

 more bushy and irregular in its mode of growth than the 

 " soft-feathered Coralline/' The branches are large and 

 spreading, and divided into a multitude of narrow scg- 



