Membranipora. Z. ASCIDIOIDA. 281 



Eschara pilosu, Pall. Eleiich. 50 Flustra pilosa, Lin. Syst. 1301. 



Mull. Zool. Dan. prod. 253. Ellis and Soland. Zooph. 1 3. Berk. Syn. 

 i. 214. Turt. Gmel. iv. 663. Wern. Mem. i. 563. Turt. Brit. Faun. 

 209. Stew. Elcm. ii. 43G. Base, Vers, iii. 140. Lam. Anim. s. Vert, 

 ii. 159. 2de edit. ii. 224. Grant in Edin. New Phil. Journ, iii. 111. 

 Flem. Brit. Anim. 537. Hogg's Stock. ,36. Bisso, L'Europ. Merid. 

 V. 335. Johnston in Trans. Newc. See. ii. 265, pi. 9, fig. 5. Lister in Phil. 

 Trans, an. 1834, 384, pi. 12, fig. 2. Templeton in Mag. Nat. Hist. ix. 



469 La F. pileuse, Blainv. Actinol. 450. 



Var. /?. The long bristle abortive or destroyed. Ellis, Corall. pi. 29, fig. 



Z). Ellis in Phil. Trans, abridg. x. 492, pi., 12. fig. 4, D Flustra 



dentata, Ellis and Soland. Zooph. 15. Turt. Gmel. iv. 664. Turt. 

 Biit. Faun. 209- Stew. Elem. ii. 436. Lam. Anim. s. Vert. ii. 158. 

 2de edit. ii. 224. Bosc, Vers, iii. 142. Stark, Elem. ii. 437. Hogg's 



Stock. 36. Temfilcton, loe. s. cit. 469 La Flustre dentee, Blainv. 



Actinolog. 450 Membranipora pilosa, Farre in Phil. Trans, an. 



1837, 412, pi. 27, fig. 1-5. 



Hub. On the lesser sea-weeds most abundant, and not uncom- 

 monly on old shells. 



Polypidora incrusting, merabrano-calcareous, irregular, follow- 

 ing- the shape and form of the objects it grows upon, straw-yellow, 

 thickish, porous, hairy : cells short, somewhat tubulous, with large 

 roundish apertures ossified and toothed on the margin, the teeth short, 

 sharp and rigid, and behind the mouth of each cell there is a very 

 long tubular bristle which issues from a hollow base like a hair from 

 its bulb. — Polypes with 12 tentacula, long in proportion to the body, 

 thick and rather clumsy. Farre. " Polypus — tentacula circiter 20, 

 sequalia et corpus sequantia, in campanse formam expandit." Pal- 

 las. 



When the polypidom encrusts the broad-leaved fuci or shells the 

 texture is thinner and the cells more completely developed, and then 

 their surface is perceived to be finely frosted. The small spines of 

 the aperture are omitted in the figure of Ellis ; and that referred to 

 for the variety dentata is imperfect and unfinished. Many believe 

 this variety to be distinct in species, and specimens, sufiiciently cha- 

 racteristic, can easily be produced in favour of the opinion, which, 

 however, 1 am satisfied is erroneous. 



M. pilosa often rises into small sponge-like fronds, cellular and 

 hirsute on each side. " In frondes lubenter assurgit, utrinque cellu- 

 losas crassiusculas, spongiosas ; primo simplices, lineares, obtusas ; 

 deinde ramosas ; imo pinnato-multifidas fere nunquam poUice longio- 

 res." Pallas. 



