90 ANTIIOZOA IIYDROIDA. 



nnilateral^ usually seated in the axilla of a horny spine ; 

 vesicles scattered, unilateral. — Polypes hydraform. 



* Stem a single tube. 



1. P. FALCATA, stem waved, branched; branches alternately 

 pennated ; cells close-ranhed, shortly tubulous with a plain rim ; 

 vesicles oblong-oval, Merrett.* 



Plate XXI. Fig. 1, 2. 



Muscus marinus spiralis pennatus, Merr. Pin. 81. — Corallina muscosa peiinata, 

 raniulis et capillamentis falcatis, Ruii Syn. i. 36, no. 16. — Muscus pennatus, 

 ramulis et capillamentis falcatis, Plukcn. Phytog. tab. 47, fig. 12. — Muscus mari- 

 tinuis pennatus, raniulis et capillamentis falcatis, Morris. Plant, hist. Ox. iii. 650, 

 tab. 9, fig. 2. — Sickle Coralline, Ellis Corall. 12, no. 11, pi. 7, fig. «, A. and pi. 

 38, fig. 6. — Corallina erecta pinnata, Bast. Opusc. Subs. 41, pi. 2, fig. 5, male. — 

 Sertularia falcata, ZiM. Syst. 1309. PaU. Elench. 144. Ellis -awA Sohmd. Zoopli. 

 42. Esper Pflanz. Sert. tab. 2, fig. 1, 2. Berk. Syn. i. 217. Blumciib. Man. 

 273. — Aglaophenia falcata, Lamour. Cor. Flex. 174. — Plumularia falcata, Lam. 

 Anim. s. Vert. ii. 125 : 2de edit. ii. 160. Grajit in Edin. New Phil. Journ. i. 

 155. Fle.m. Brit. Anim. 546. Johnston in Trans. Newc. Soc. ii. 259. Hassull 

 in Ann. and Mag. N. Hist. vi. 1G9. Couch Zooph. Cornw. 14 : Corn. Faun. iii. 30. 



Hah. On shells and rocks near low-water mark, and in deep 

 water. 



A common and very elegant species, generally from four to 

 six inches in height, sometimes attaining to twelve, rising in wide 

 spiral turns, and sending out from its filiform percurrent stem, at 

 regulated intervals, alternate spreading plumous branches wliich 

 are placed one above the other on the outer side. Pinna) alternate, 

 bifarious. lu young specimens the branches are two-ranked and 

 alternate, and I have seen this character remain in one specimen 

 of considerable size. There are no cells on the spiral stem, but 

 they occur on the branches as well as on the pinnse, and are ar- 

 ranged in two rows pointing alternately to opposite sides. There is 



Lamarck avait mis genereusement a sa disposition toutes les richesses de cet etii- 

 blissement deja denominees et classees par sea soins." — Ann. des Sc. Nat. Part. Zool. 

 torn. vi. second ser. p. 12. 



* For an account of Dr. Christopher Merrett, see Wood's Athen. Oxon. v. ii. 

 p. 930 ; Pulteney's Sketches, v. i. p. 290, &c. ; and Thomson's Hist, of the Roy. Soc. 

 p. 22. He was bom in 1614 ; was one of the original members of the Royal Society ; 

 and died in 1695. Ray's character of him in 16fJ8 is — " Annis et scientia gravis, de 

 Professione sua deque Repub. Botanica optirae meriti." Hist. Plant, prsef. Contrast 

 this with the character in Sir J. E. Smith's Eng. Flora, i. pref. vii-viii. Those who 

 care to study Merrett's character may, perhaps, find a key to it in the " Epistola ad 

 Lectorem" of the Pimix. 



