CAMBRIC. 



[ 130 ] 



CAMPTOCERCUS. 



closed between the wood and vessels of in- 

 dividual bundles, so that their growth is 

 limited. The cambium of the outside of 

 the wood of Dicotyledons forms new layers 

 of liber, in most cases, on the inside of the 

 old ones, pari passu with the development 

 of the layers of wood. Cambium, which 

 is in great part only an early and trans- 

 itional form of cellular tissue, afterwards 

 to become developed into wood, is com- 

 posed of delicate cellulose cells enclosing 

 a primordial utricle, nucleus, and abun- 

 dance of nitrogenous protoplasm, but usually 

 without chlorophyll. The cells multiply 

 b} r transverse division in the elongation of 

 the stem, and by perpendicular division 

 ( tangential and radial) as the stem expands 

 in diameter. This process is effected by 

 the constriction of the primordial utricle 

 and gradual development of a septum, as 

 in ordinary vegetative cell-development. 

 The cambium of most Dicotyledons is gra- 

 dually matured into wood from within 

 outwards ; but in the Monocotyledons and 

 Flowerless Cormophytes it often remains in 

 great part in a delicate and soft condition, 

 forming the vasa propria of Mohl. Owing 

 to the delicacy of its structure, cambium 

 was formerly imagined to be a thick muci- 

 laginous fluid poured out in the growing re- 

 gions of plants (as between the wood and 

 liber of Dicotyledonous stems in spring) ; 

 which by degrees becomes organized and 

 converted into cellular tissue, by the inde- 

 pendent origin and subsequent coalescence 

 of a number of cells generated in this fluid. 

 This erroneous view was strongly supported 

 by Mirbel and others. 



BIBL. Treviranus, Phys. d. Gewachse, i. 

 159; Mirbel, Ann. d. So. N. 2 ser. xi. 321, 

 xix. 197; Payen, C'ompt. Rend. 1839; Schlei- 

 den, Botanik ; Henfrey-Masters, Botany ; 

 Nageli, Zeitsch. f. wiss. Bot. iii. 64, & Mikr. 

 576; M.oh},Veaetab.ZeUe(Transl.y, Schacht, 

 Pflanzenzelle ; Sachs, Bot. 83. 



CAMBRIC. This name was formerly ap- 

 plied strictly to the finest kind of linen cloth. 

 It is used now in a loose sense in trade. 

 French cambric, however, ought to be linen. 

 Scotch and English cambrics are commonly 

 made of cotton, while Indian cambric is 

 made of the grass-cloth fibre. The fibres 

 may be distinguished under the microscope, 

 and the value of the fabric thus ascertained. 

 See FIBROUS SUBSTANCES and COTTON. 



CAMERA LUCIDA. INTRODUCTION, 

 p. xxii. 



CAMPANULA'RIA, Lamk. A genus 



of Hydroid Zoophytes; family Campanu- 

 lariidee. 



Distinguished by the creeping or erect 

 polypidom, the filiform continuous main 

 tube, giving off its stalked and campanulate 

 cells irregularly or in whorls, the usually 

 long, ringed stalks, and the scattered, ses- 

 sile vesicles. 



Hincks defines the genus thus : Stems 

 simple or branched ; cells bell-shaped and 

 hyaline, without operculum ; polypes with a 

 large cup-shaped proboscis; germ-cells borne 

 on the stems or the creeping stolon, with 

 fixed spore-sacs. 13 species; 3 doubtful. 



C. volubilis (PI. 41. fig. 4). Stem a 

 single tube, creeping, filiform ; cells on long, 

 slender ringed stalks, campanulate, with a 

 serrated margin; vesicles ovate, wrinkled 

 concentrically. Parasitic on sea- weeds &c. ; 

 frequent. It forms an elegant microscopic 

 object. 



C. dumosa. Stem compound, erect or 

 climbing, irregularly branched; cells long, 

 tubular, patent, almost sessile, orifice entire. 

 In deep water. 



BIBL. Johnston, Brit. Zooph. 107; Gosse, 

 Mar. Zool. i. 24 ; Hincks, Brit. Zooph. 

 160. 



CAMPANULAR'IID^, Johnston. A 

 family of marine Hydroid Zoophytes. 



Char. Those of Sertulariidse,' but cells 

 stalked. 



Genera: Campannlaria, Laomedia. 



Hincks revises the family thus: Cells 

 terminal, stalked, campanulate ; polypes 

 with a large trumpet-shaped proboscis. 

 And admits the genera Clytia, Obelia, Cam- 

 panularia, Lovenella, Thaumantias, and Go- 

 nothyrcea. 



BIBL. Johnston, Brit. Zooph. ; Gosse, 

 Mar. Zool. i. ; Hincks, Br. Zooph. p. 137. 



CAMPANULI'NA, Van Beneden. A 

 genus of marine Hydroid Zoophytes ; family 

 Campanulinidae. 



Char. Stem simple or branched, rooted ; 

 cells pointed above; polypes cylindrical, 

 with webbed tentacles ; reproduction by 

 free medusa-buds, single in each capsule. 

 3 species. 



BIBL. Hincks, Brit. Zooph. p. 186. 



CAMPANULI'NID^E. A family of 

 Polypi, order Hydroida. 



Char. Cells ovato-conic, stalked; polvpes 

 long, cylindrical, with a small conical pro- 

 boscis. 



Genera : Campanulina, Zygodactyla, Oper- 

 cularella. 



CAMPTOCER'CUS, Baird (Lynceus 



