CORNICULARIA. 



[ 170 ] 



CORYNEUM. 



filled with starch, which makes up the great 

 body of the grain ; a few layers of cells sub- 

 jacent to the surface, however, contain little 

 starch, but abundance of nitrogenous proto- 

 plasmic matter, or gluten. These layers 

 containing the greater proportion of the 

 gluten, together with epidermis, are removed 

 from fine flour in grinding, as the bran and 

 pollard, the fine white flour consisting chiefly 

 of the starch. The forms of the starch-grains 

 diffier considerably, as also their condition in 

 the cell. In Wheat "( Tnh'cwm), the starch - 

 grains are lenticular (PI. 36. fig. 8), and lie 

 loose in the cells; in Barley {Hordeum), 

 they are somewhat discoidal, with a thicker 

 rim (PI. 36. fig. 9) ; in Oats (Avena), poly- 

 gonal, but compacted together into roundish 

 masses (PI. 36. fig. 10), in both cases also 

 free in the cells ; in Rice ( Oryza), the starch- 

 grains are very small, and packed so closely 

 together that they press upon one another, 

 thus acquiring a parenchymatous form (PI. 

 36. figs. 12 & 13); and then, as they adhere 

 firmly together, the contents of the cells ap- 

 pear like one solid mass ; hence the horny 

 character of the grains of rice, and the grit- 

 tiness of rice-flour. In Maize (Zea), the 

 outer part of the grain is horny from the 

 same cause as rice, and presents a similar 

 appearance (PI. 36. fig. 3), but in the centre 

 the cells are often less densel}^ filled, and the 

 grains lie more or less loose (PI. 36. fig. 5). 

 For further particulars of the characters of 

 the starch-grains, see Starch. 



CORNICULARIA, Ach.— A genus of 

 Parmeliacese (Gymnocarpous Lichens) com- 

 posed of rigid tufted plants, the lobes of the 

 thallus standing up in forked horn-like pro- 

 cesses. Most of the species occm* on the 

 ground or rocks on high mountains. 



BiBL. Hook. Br. Fl. ii. pt. 1. 232; Engl. 

 Botany, pi. 452. 846. 720, &c. 



CORNS — consist of thickened epidermis, 

 the scales being increased in number, much 

 flattened, and closely aggregated from pres- 

 sure. This is the structure in their simplest 

 form. When larger, they represent an ordi- 

 nary blister, conjoined with the thickening 

 of the epidermis ; hence the origin of the 

 cavity in the centre of many of them. The 

 papillae of the cutis are generally hypertro- 

 phied. The epidermic scales may be ren- 

 dered distinct by digestion with acetic acid 

 or solution of potash. 



CORPORA AMYLACEA. — These are 

 microscopic rounded bodies, exhibiting a 

 number of concentric rings, and somewhat 

 resembling starch-grains in appearance (PI. 



30. fig. 23). They are found in the fornix, 

 the septum lucidum, the walls of the ventri- 

 cles, and the cortical substance of the brain, 

 the medullary substance of the spinal cord, 

 the waxy spleen, &c. They are but little 

 acted upon by dilute acids ; caustic alkalies 

 render them more transparent, and gradually 

 dissolve them. Solution of iodine gives them 

 a bluish tinge, and the subsequent addition 

 of sulphuric acid produces the bluish-violet 

 colour seen when cellulose is treated with 

 these reagents. The reaction is best seen 

 when the action of the acid takes place 

 slowly. Hence these bodies have been re- 

 garded as consisting of cellulose. It has 

 been objected, that as cholesterine gives si- 

 milar reactions, and occurs in those places 

 where the corpora amylacea are met with, 

 the reactions might arise from the presence 

 of this substance. The former view is, how- 

 ever, probably correct. 



The corpora amylacea must be distin- 

 guished from the concretions forming 'brain- 

 sand,' or the acervulus cerebri. These are 

 also rounded, single, or aggregated, usually 

 exhibiting the concentric rings, sometimes 

 forming cylindrical, ramified, or reticular 

 fibres. They are met mth in the choroid 

 plexuses, the pineal gland, the arachnoid 

 membrane, and sometimes in the walls of 

 the ventricles. These consist of an organic 

 (proteine) skeleton, containing carbonate 

 and phosphate of lime. When treated with 

 acids, the latter are dissolved, the former 

 bemg left, and retaining the original form of 

 the concretions. 



The relation of the corpora amylacea and 

 the acervulus cerebri to the colloid cor- 

 puscles, if any exist, has not been deter- 

 mined. 



BiBL. Purkinje, Muller^s Archiv, 1836 & 

 1845; Kolhker, Mikr. Anat. ii. pt. 2. 501 ; 

 Virchow, Archiv f. Path. Anat. 4'C- p. 135, 

 268, 416, and Ann. Nat. Hist. xii. p. 481. 



CORPUSCULA, of the Coniferee. See 

 Gymnospermia. 



CORROSIVE SUBLIMATE. See Mer- 

 cury, Bichloride of. — A saturated solu- 

 tion of this salt is very useful in rendering 

 very transparent bodies consisting of pro- 

 teine-compounds more opake and distinct, 

 as the bodies and cilia of Infusoria, &c. 



CORYNEUM, Kunze.— A genus of Me- 

 lanconiei (Coniomycetous Fungi), consisting 

 of parasitic plants growing upon dead twigs, 

 bursting out as convex solid pustules from 

 beneath the epidermis. A vertical section 

 of half of one of these pustules is shown 



