CRYPTONEMIACE.E. 



[ 176 ] 



CRYSTALLOGRAPHY. 



chotomous, horny, of very dense structure. 

 Tetraspores strung together, contained in 

 superficial wart-like sori. 



VIII. Polyides. Root scutate. Frond 

 cylindrical, dichotomous, cartilaginous. Fa- 

 vellcB contained in spongy external warts. 

 Tetraspores scattered through the peripheric 

 stratum of the frond, cruciate. 



IX. Furcellaria. Root branching. 

 Frond cylindrical, dichotomous, cartilagi- 

 nous. Favellce unknown. Tetraspores deeply 

 imbedded among the filaments of the peri- 

 phery, in the swollen pod-like upper branches 

 of the frond, transversely zoned. 



Subtribe 3. GASTROCARPE.E. Frond 

 gelatinously membranaceous or fleshy, often 

 of lax structure internally. Favellidia im- 

 mersed in the central substance of the frond, 

 very numerous. 



X. Dumontia. Frond cylindrical, tubular, 

 membranaceous. Tufts of spores attached 

 to the wall of the tube inside. 



XI. Halymenia. Frond compressed or 

 flat, gelatinoso-membranaceous, the mem- 

 branous surfaces separated by a few slender, 

 anastomosing filaments. Masses of spores 

 attached to the inner face of the membra- 

 nous wall. 



XII. Ginannia. Frond cylindrical, dicho- 

 tomous, traversed by a fibrous axis; the 

 walls membranaceous. Masses of spores 

 attached to the inner face of the membra- 

 nous wall. 



XIII. Kallymenia. Frond expanded, leaf- 

 like, fleshy -membranous, solid, of dense 

 structure. Favellidia like pimples, half im- 

 mersed in the frond, and scattered over its 

 surface. 



XIV. Iridcea. Frond expanded, leaf-like, 

 thick, fleshy-leathery, solid, of dense struc- 

 ture. Favellidia wholly immersed, densely 

 crowded. 



XV. Catenella. Frond filiform, branched, 

 constricted at intervals into oblong articula- 

 tions ; the tube filled with lax filaments. 



Subtribe 4. GLOIOCLADIE^E. Frond 

 loosely gelatinous, the filaments of which it is 

 composed lying apart from one another, sur- 

 rounded by a copious gelatine. Favellidia 

 immersed among the filaments of the peri- 

 phery. 



XVI. Cruoria. Frowrfcrustaceous, skin-like. 



XVII. Naccaria. Frond filiform, solid, 

 cellular ; the ramuli only composed of radi- 

 ating free filaments. 



XVIII. Gloiosiphonia. Frond tubular, 

 hollow ; the walls of the tube composed of 

 radiating filaments. 



XIX. Nemaleon. Frond filiform, solid, 

 elastic, filamentous; the axis composed of 

 closely-packed filaments; the periphery of 

 moniliform free filaments. 



XX. Dudresnaia. Frond filiform, solid, 

 gelatinous, filamentous; the axis composed 

 of a network of anastomosing filaments ; the 

 periphery of moniliform free filaments. 



XXI. Crouania. Frond filiform, consist- 

 ing of a jointed filament, whorled at the 

 joints with minute, multifid, gelatinous ra- 

 muli. 



BIBL. Harvey, Marine Alga-, Derbes et 

 Solier, Ann. des Sc. nat 3 ser. xiv. 273. 

 See also the Genera. 



CRYPTOSPORIUM, Kze. A genus of 

 Sphaeronemei (Coniomycetous Fungi). Mi- 

 croscopic Fungi growing upon bark and 

 leaves, producing spindle-shaped spores, at 

 first conglutinated beneath the epidermis of 

 the nurse-plant. Two species have been re- 

 corded as British. 



1. C. Caricis, Corda. Heaps of spores 

 punctiform ; spores slightly curved, dark 

 brown and pellucid. On leaves of various 

 sedges. Corda, apud Sturm, Deutschl. Flor. 

 t. 1. 



2. C. vulgare, Fries. Heaps confluent ; 

 spores curved, black (subhyaline). On dead 

 twigs of birch, hazel, alder, &c. Corda, I.e. 

 t. li. (Mr. Berkeley thinks this not con- 

 generic with C. Caricis.) 



BIBL. Berkeley and Broome, Ann. of Nat. 

 Hist. 2 ser. v. p. 3/1 ; Fries, Syst. Myc. iii. 

 p. 481. 



CRYSTALLINE, or CRYSTALLINE 

 LENS. See EYE. 



CRYSTALLOGRAPHY. The laws of 

 crystallography teach us that in perfectly 

 formed crystals, each peculiar chemical com- 

 bination corresponds to a distinct relation of 

 all the angles which can possibly arise from 

 the primary form ; hence by ascertaining the 

 latter, we can infer the former. It was our 

 intention to have given a sketch of the me- 

 thod of determining the primary forms of 

 the most common microscopic crystals, and 

 the systems to which they belong ; but our 

 space is far too limited for this purpose, so 

 that we must rest satisfied with a reference 

 to works specially devoted to the subject. 



The angular inclination of the facets of 

 small crystals is in many cases easily deter- 

 mined, by viewing the crystals in all posi- 

 tions, and measuring the angles with the 

 GONIOMETER. When possible, the crystals 

 should be held by the forceps, or fixed to 

 them by the aid of melted wax, or Canada 



