76 ANTHOZOA HYDROIDA. 



stem flattened, slightly zigzag; the branches rather close, linear, 

 alternate, bifarious, simple, or sometimes pinnated : Cells generally 

 semialternate, rather small, bellied at the base with a narrow 

 everted neck and plain aperture, so as somewhat to resemble a 

 Florence-flask : Vesicles scattered, subsessile, proportionably small, 

 smooth, ovate, with an even shortly tubulous mouth : they are pro- 

 duced principally in the winter season, when they are sometimes " in 

 such abundance as almost to cover the denticles, but placed in 

 a very regular order," Ellis ; and always on the upper edge of the 

 branch from which they originate. 



14. S. FiLicuLA, celU of the form of a Florence-flask, op- 

 posite, a single one in the axilla of each pinna ; vesicles pear- 

 shaped, smooth, the aperture shortly tubulous, entire. Hudson.* 



Plate XIV. Fig. 1, 1. 



Sertiilaria filicula or Fem Coralline, Ellk and Soland. Zooph. 57, pi. 6, fig. c C 

 TuH. Brit. Faun. 215. Bees' Cyclop. Vermes, pi. 8, fig. 1. Jameson in Wem. 

 Mem. L 564. Zam. Anim. s. Vert. ii. 119. Zajnoar. Cor. Flex. 188. Johnston 

 in Trans. Newc. Soe. ii. 257. Thompson in Ann. Nat. Hist. v. 250. Hassall in 

 Ann. and Mag. Nat. Hist. vii. 284. Couch Comw. Zooph. 9 ; Com. Faun. iii. 23. 

 — S. abietina,/3, Pall. Elench. 134. — Dynamena filicula, i^fcm. Brit. Anim. 544. 



Hah. — Parasitical on sea-weeds, particularly on the entangled 

 roots of Laminaria digitata. From the observations of Mr. W. 

 Thompson, it seems to be partial to bivalve shells on the coast 

 of Ireland ; and it is also met with on Flustrge. It is not an abun- 

 dant species, but is generally distributed. 



Polypidom arising from a creeping fibre, one to four inches in 

 height, spreading bifariously, irregularly branched, slender and 

 flexible, of a straw-yellow or brownish colour, homologous through- 

 out ; the rachis zigzag, or " bent to and fro into alternate angles," 

 closely pinnated, the pinnae shooting from every bend alternately on 

 opposite sides, linear, patent, simple or composite : Cells closely set, 

 minute, giving a serrulated appearance to the ramifications of the 

 polypidom, shaped something like a Florence-flask, smooth, the 

 aperture oblique, entire : The vesicles are rarely produced, nor have 



* William Hudson, a London apothecary, elected F.R.S. in 1761 : the author of 

 the "Flora Anglica," the publication of which, in 1762, "marks the establishment of 

 Linntean principles of Botany in England, and their application to practical use." — 

 Sir. J. E. Smith. 



