97 



polypidom is divided into internodes of nearly equal lengths, 

 and about three times as long as the transverse diameter; 

 these, however, are hardly visible but in dried specimens. 

 The cells are oval, numerous, crowded, sub-pedunculated, 

 and not congregated into companies. They are somewhat 

 irregular in size, but are generally about twice as long as 

 the diameter of the branch. The polypes are very active 

 with eight ciliated tentacula. 



There are several discrepancies between this account, and 

 those given by Ellis, Fleming, Thompson and Johnston, but 

 if we suppose their descriptions to have been taken from in- 

 jured specimens, this in a similar condition closely resembles 

 them, otherwise it must be considered a new species. 



CRISIAD.E. 



Polypidom calcareous, or sub-calcareous, branched, con- 

 fervoid, jointed ; the cells linked together in one or more 

 series, distinct, tubular or elliptical, with a terminal or sub- 

 termiual aperture, never closed with an operculm. 



CRISIA. Lamouroux. 

 Generic Character: Polypidom confervoid, rooted by tu- 

 bular fibres, dichotomously branched ; the cells long and 

 tubular, linked together in one or two series, the apertures 

 round, terminal, and produced. Polypes ascidian. 



* Cells linked in a single series. 



GOATS-HORN CORALLINE. Crista Cornuta. Cells 

 long and tubulous, with a curved termination, having a 

 long bristle at the joint above each cell. PI. 17, fig. 4. 



Goat's-horn Coralline, Ellis' Coral., p. 42, no. 10, pi. 21, 

 fig. c C. Cellaria cornuta, Ellis and Solander's Zooph., 

 p. 25. Sertularia cornuta, Stewart's Elem., vol. 2, p. 449. 

 Turton's Lin., vol. 4, p. 686. Eucratea cornuta, Lamou- 

 roux's Coral. Flex., p. 149, no. 260. Fleming's Brit. An., 

 p. 541. Crisia cornuta, Johnston's Brit. Zooph., p. 260, 

 pi. 31, figs. 1 and 2. Templeton in Mag. Nat. Hist., vol. 9, 

 p. 469. 



Hab. On fuci and corallines, rare ; on the sides of the 

 Corwich crab mixed with Crisia eburnea, common. Pol- 

 perro, Lake Rock, Mevagissey and Whitsand bays. 



It is calcareous, confervoid, about half an inch in height, 

 and is formed of a single row of cells, bent near their aper- 

 tures, and placed one above another; it is slender, erect, 

 very brittle, alternately branched, and rooted by calcareous, 

 tubular creeping fibres. Above the beaked termination of 

 each cell is a long bristle, which is generally broken oflf in 

 preserved specimens. The apertures of the cells are even 



