BUGTJLA PURPTJROTINCTA. 89 



arm again dividing and subdividing^ and the ultimate 

 ramules forming a number of curled, tendril-like claspers 

 (Plate XII. figs. 6, 7), by means of whicli we may sup- 

 pose tbe slender tufts fix themselves or cling to some 

 neighbouring support. These prehensile appendages are 

 distributed in great numbers over the zoariima, ranging 

 from its upper portions to its very base. The tuft com- 

 mences with one or two cells, disposed in single series ; 

 and two of the appendages spring one on each side from 

 the primary cell, close to its lower extremity. 



We have in this case another adaptive modification of 

 the simpler structure, correlated, in all probability, with 

 some peculiarity of habitat. I have never met with any 

 trace of the ordinary radical tubes on B. uncinata ; the 

 appendages abound on the lowermost portion of the shoots ; 

 and in all cases it is more or less invested by some fibrous 

 material, in which the base of the zoarium was probably 

 plunged, and to which it was fast bound by its apparatus 

 of hooks'^. 



BuGULA PURPUROTiNCTA, Norman, 



Plate XII. figs. 8-12. 



Cellulaeia fastigiata, Balyell, Eare and Eem. An. Scotl. i. 236, pi. xlvi. 



{not the Sertularia fastigiata of Fabricius). 

 Cellularia plumosa, Johnst. B, Z. ed. 2, 341, pi. La. : Sars, Reise i Lofoten 



og Fium. 29. 

 BuGULA fastigiata, Alder, Cat. Zooph. North, and Durh. 59 : Sars, Geol. 



og Zoolog. Reise i sommeren 1862, 37. 

 BuGULA avicularia, fonna fastigiata (part.), Smitt, Krit. Fort., CEfv. 



Vetensk.-Akad. Forhandl. 1867, 291 and 346, pi. xviii. 



figs. 16-18. 

 BuGULA PURPUROTINCTA, Novman, Quart. Journ. Micr. Sc. (n. s.) viii. 219. 



Zoarium stout, bushy, irregularly branched, of a purplish- 



* In the footnote on page 30, the name of the present species should be 

 substituted for B. iilumosa. 



