Plumularia. Z. HYDROIDA, 143 



so many minute grey coloured stars, having the interstices between 

 the rays filled with a colourless transparent matter, which seems to 

 harden into horn. The grey matter swells in the centre, where the 

 rays meet, aud rises perpendicularly upwards surrounded by the trans- 

 parent horny matter, so as to form the trunk of the future zoophyte. 

 The rays first formed are obviously the fleshy central substance of the 

 roots, and the portion of that substance which grows perpendicularly up- 

 wards, forms the fleshy central pai'tof the stem. As early as I could 

 observe the stem, it was open at the top ; and, when it bifurcated to 

 form two branches, both were open at their extremities, but the fleshy 

 central matter had nowhere developed itself as yet into the form of a 

 polypus. Polypi, therefore, are not the first formed parts of this 

 zoophyte, but are organs which appear long after the formation of the 

 root and stem, as the leaves and flowers of a plant." Professor Grant. 



2. P. CRiSTATA, shoots simple, plumoiis, the pinna alternate ; 

 cells in a close roio, cup-shaped ivitii a toothed margin and a short 

 lateral spine ; vesicles gibbous, girt with crested ribs. Ellis. 

 Plate XIX. Fig. 1—3, and Plate XX. Fig. 1. 



The Podded Coralline, Ellis, Coiall. 13, no. 12, pi. 7. fig. b. B Ser- 



tularia pluma, Lin. Syst. 1.309. Pall. Elench. 149. Ellis and Soland. 

 Zooph. 43. Berk. Syn. i. 217- Tiirt. Gmel. iv. G79. Turt. Brit. Faun. 

 214. Stew. Elem. ii. 443. Bosc, Vers, iii. Ill, pi. 29, fig. 1, pe.ssima. 



Lister in Phil. Trans, au. 1834, 369, pi. 8, fig. 2 Aglaophenia pluma, 



Lamour. Cor. Flex. 170- Corall. 75 Plumularia eristata, Lam. Anim. 



s. vert. ii. 125. 2de edit. ii. 161. Stark, Elem. ii. 440. Templeton'm Mag. 



Nat. Hist. ix. 467. Risso, L'Europ. merid. v. 313 PI. pluma, Flem. 



Brit. Anim. 546 La Plumulaire plume, Blainv. Actinol. 477 



Sertolaria pluma, CavoL Pol. mar. 210, tav. 8, fig. 5 — 7. 



Hah. On Fuci, particularly Fucus siliquosus, and sometimes " on 

 muscles and other shells." Common on the southern coasts of Eng- 

 land. Picked up on the shox'e at Stevenston, Ayrshire, Rev. D. 

 Landsborough. On the coast of Ireland near Dublin, Ellis. On 

 the shore of Belfast Lough, &c. 3Ir TempJeton. 



Attached to sea-weeds by a flexuous horny anastomosing tubular 

 fibre, which throws up, at intervals, plumous shoots from one to one 

 and a half inch high : these are very elegant and erect when in the 

 sea, but when dry become curved in a falcate manner with all their 

 pinules, which are also frequently laid to one side. " Siccatione 

 surculi sursum seu contrario modo qiiam fuerant, recurvantur, pin- 

 nulseque curvatae ad invicem accedunt." Pallas. The polypidom is 

 of a honey-yellow colour with a dark brown rachis, which is smooth, 

 and divided by numerous oblique septa or joints, there being one be- 



