FLUSTEA SECURIFRONS. 



121 



the Bass Rock (Landsb.): Oban (T. H.) : Firth of Forth, 

 30 fathoms (Kirchenpauer): Northumberland and Durhaiii, 

 abundant (Alder) : two miles east of Sana Island, in 40 

 fathoms (Hyndman) : 8 miles S.S.W. Mull of Galloway 

 (Capt. Beechey) : Filey, plentiful (T. H.) : Dublin Bay 

 (Templeton) : Belfast Bay (W. T.) : coast of Antrim, 

 20 fathoms (Mr. W. Swanston). 



Var. [papijracea, Dalyell) '' with the ends expanded 

 into undulating foliations, from the fusion of several of 

 the terminal branchlets into one." Scotland (Dalyell) : 

 Northum berlaud (Alder) . 



Geographical Distribution. Mediterranean (Pallas) : 

 Adriatic (Heller) : Lofoten ; near Tromso and Havosund, 

 in 40-50 fathoms, rare (M. Sars) : Spitzbergen ; western 

 coast of Skandinavia, 10-50 fathoms (Smitt) : ibid. 150- 

 300 fms. (Koren) : South Labrador, frequent (Packard). 



This species forms very large bunches, of a light straw- 

 colour when fresh. 



In many specimens " wedge-shaped leaflets " are deve- 

 loped along the edges of the segments composing the 

 zoarium. 



The ovicell, as in all the species of this genus, is 

 inclosed within the walls of the cell above it, and overlaid 

 with its membranous covering, so as to be quite inconspi- 

 cuous. Indeed, the ovicell itself is all but in- 

 visible ; the arch in front of it and the aperture 

 are the only signs of its existence which strike 

 the eye. The latter is filled in by a membrane, 

 and is also protected by two rib-like appen- 

 dages, which are given off one on each side 

 of it, and meet in the centre. The ooecium of 

 this species is larger and more fully developed 

 than that oi Flustra foHacea (woodcut, fig. 6). 



Fig 6. 



Ooecium. 





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