22 



have been procured. It varies in height from fonr to twelve 

 inches, but the Cornish specimens did not exceed six. It is 

 rather delicate, and of a semi-transparent horn colour in- 

 clining to pink when living, changing to a deeper and duller 

 colour in dyin?. The branches, which are widely separated 

 from each other, are given off alternately. The cells are 

 opposite, pellucid, attached to the polypidora by the base, 

 the upper half being free and divergent, and distributed in a 

 biserial manner; their apertures are patulous, with two lateral 

 tooth-like inequalities. The vesicles are unilateral and arise 

 from the base of the upper row of cells; they are shortly pe- 

 dunculated, stout, longitutinally furrowed, and their apertures 

 are small and tubular. They vary in shape according to age. 

 When young they are urn shaped wiih tubular apertures; a 

 little older, the rim at the base of the neck becomes enlarged 

 and sharp-edged, with two small bo»*ns ; when old, the neck 

 and mouth disappear after the ova have escaped, and the 

 margin becomes irregularly festooned. 



SEA FIR. S. Abietina. Cells very nearly opposite, 

 tubular, slightly bellied at the b-ise; mouth simple and 

 unarmed ; the upper half free : vesicles ovoid with a neck. 



Corallina marina Abietis forma. Muscus marinus major 

 argute denticulafis Raii Synop. Stirp., vol. 1, p. 35, no. 12, 

 Sea Fir, Ellis' Cor., p. 4, pi. 1, fig. b, B., no. 2. Dyna- 

 roena Abietina, Fleming's Brit. An., p. 543. Sertularia 

 Abietina, Ellis aud Solander's Zooph,, p. 36, no. 2. La- 

 mouroux's Cor. Flex., p. 18G and 187. Turton's Lin., vol. 4, 

 p. 676. Blumenbach's Man., p. 273. Stewart's Elem vol. 2, 

 p. 441. Templelon in Mag. Nat. Hist., vol. 9, p. 466. John- 

 ston's Brit. Zooph., p. J30, pi. x., fig. 1. 1. 



Hab. On stones, shells and Gorgonia verrucosa, common, 

 from deep water. In the Fowey river, on stones and shells. 



This species varies in height from four to eight inches, 

 growing in great luxuriance on Pinnce, at from six to nine 

 leagues south of the Deadraan poiut; and less so near the 

 shores, where it is generally in an injured state, having the 

 branches and cells knocked off by the violence of the waves. 

 In a perfect state the polypidom is of a light brown colour, 

 polished, compressed laterally, slightly bent, and has cells 

 both on the branches and trunk. The branches which are 

 about as large as the trunk, arise in an alternate manner, and 

 more closely together than in the last species. The cells are 

 semi-alternate, bellied at the base, with contracted and 

 everted apertures, and are attached only at the base, the 

 upper portion being free and diverging. The vesicles, which 

 are few in number, small, and irregularly distributed, arise 



