342 POLYZOA INFUNDIBULATA. 



ture of the apertures in living specimens to justify an attempt, on 

 my part, to characterize them. Dr. Fleming's name Tricellaria 

 might be applied to the first section, but it would convey a false idea 

 of the structure of one of the species : Scrupocellaria is applied by 

 Van Beneden to the second section, but a barbarous name that violates 

 every canon of nomenclature ought to be rejected : when the third 

 section is named and defined generically, Flustra avicularis and mur- 

 rayana will require to be removed to the genus : and Acamarchis of 

 Lamouroux remains for the species of the fourth section. 



16. FLUSTRA,* Linnseus. 



CHARACTER. Polypidom plant-like, membranous, frondose 

 or crustaceous, formed of cells arranged quincuncially in several 

 series and in one or two layers : cells in juxtaposition, more or 

 less quadrangular, fiat, with a distinct border ; the aperture 

 transverse, semilunar, valvular, subterminal.-\ 



* Foliaceous, with cells on both sides. 



1. F. FOLIACEA, cells narrow at the proximal and arched at 

 the distal extremity, with scattered marginal denticles. . 



PLATE LXII. FIG. 1, 2. 



Fucus marinus scruposus albidus telam sericeam texturA sua aemulans, Morris. Hist- 

 Plant, iii. 646, tab. 8, fig. 16. (bona.) Fucus telam lineam sericeamve textura sua 

 semulans, Raii Syn. 42, no. 9. Jussieu in Mem. Acad. Roy. des Sc. 1742, 298, 

 pi. 10, fig. 3. Broad-leaved Hornwrack, Ellis Corall. 70, no. 2, pi. 29, fig. a, A. 

 B, 6. Curious sea- weed, Hooke Microg. 140, pi. 9, fig. 2 ; and pi. 14, fig. 1. 

 Eschara foliacea, Lin. Syst. edit. 10, 804. Pall. Blench. 52. Flustra foliacea, 

 Lin. Syst. 1300. Mull. Zool. Dan. prod. 253. Ellis and Soland. Zooph. 12, pi. 2, 

 fig. 8. Esper Pflanz. Flust. tab. 1, fig. 1, 2. Van Beneden Recherch. 56, pi. 7, 

 fig. 11-17. Berk. Syn. i. 214. Lam. Anim. s. vert. ii. 156: 2de edit. ii. 219. 

 Grant in Edin, New PhiL Journ. iii. Ill and 337. Flem. Brit. Anim. 535. 

 Johnston in Trans. Newc. Soc. ii. 263. Mag. Nat. Hist. iii. 483, fig. 120. Tem- 



* From the Saxon Fluslrian, to weave : hence Flustra applied by Linnaeus to 

 these sea-mats. 



f " The aperture of the cells is formed by a semicircular lid, convex externally and 

 concave internally, which folds down when the polypus is about to advance from the 

 cell. The opening of this lid in the F. truncata, where it is very long, appears 

 through the microscope like the opening of a snake's jaws, and the organs by which 

 this motion is effected are not perceptible. The lid of the cells opens and shuts in 

 Flustrae, without the slightest perceptible synchronous motion of the Polypi." Grant 

 in Edin. New. Phil. Journ. iii. 339. 



