21 



elongated peduncles, which arise from the base of the cells. 

 Their apertures are terminal, unarmed and contracted ; 

 when recent and living they are smooth, but are frequently 

 marked, when preserved, with longitudinal furrows. This 

 form of the vesicle is rarely observed except when it has 

 arrived at perfection, but in a less advanced state the uppep 

 portion is flat, and the circumference irregularly lobulated. 

 They only arise from the upper edge of the pinnae, and are 

 all turned to the same side of the fan of the polypidom. 

 This species, as it is seen in collections, is of a dark or 

 black-brown colour, from which it derives its specific name; 

 but to see it in all its beauty it must be examined in a living 

 state and soon after it is taken from the sea; when instead 

 of being black, it will be found of a beautiful and delicate 

 pink, and in some instances of a deep arterial blood colour. 

 It is the stoutest and most rigid of all our native Sertularige, 

 but there are several others which exceed it in beauty 

 and delicacy, Though not so generally diffused as many 

 others, it is far from being uncommon in particular localities. 

 Off the Dead man-point it is found, though rarely ; at a few 

 miles west and north-west of the Eddystone lighthouse it 

 is common, and from that locality [ have obtained some 

 exceedingly fine specimens, which, from January to May, 

 have abounded in ovarian vesicles. It is firmly rooted to 

 the stone on which it grows, by tubular matted fibres, of a 

 deeper tint than the other parts. On the lower portion, 

 the Campanularia dumosa is frequently abundant. 



According to Johnston, Milne Edwards supposes there 

 are two species confounded under this name. The species, 

 however, that I have found in the Cornish waters is the 

 same as that figured by Johnston at pages 1 19 and 12.9, 

 though I have not observed the irregularity in the distribution 

 of cells on the pinnae, or the form of the apertures of those 

 on the trunk, figured and noticed by him. 

 SEA TAMARISK. S. Tamarisca. Cells opposite, tu- 

 bular; the upper half divergent, with a wide aperture, 

 sinuated on the margin; vesicles oval, truncate, with two 

 small points on the corners, and a tnhulous mouth. 

 Sea Tamarisk, Ellis' Coral., p. 4, no. I, pi. 1, fig. a A. 

 Sertularia Tamarisca, Ellis and Solander, p. 3{>, no. I. 

 Turtnn*s Lin., vol. 4, p. 67b". Stewart's Eiem., vol. 2, p. 441. 

 Johnston's Brit. Zoopb., p. 130, pi. x, figs. 2, 3, and 4. 

 Lamouroux's Cor. Flex., p. 188, no. 313. Dynamena Tama- 

 risca, Fleming's Brit. An,, p. 543. 



Hab. On the Pinna Ingens, from deep water, rare. 

 The only locality in which this has been found is in deep 

 water off Mevagissey, and even thence only a few specimens 



c 



