IXDEX. 269 



Crustacea, Decapod. See Decapods 

 Cryptogam ia, spores of, i. 177, 178 

 Cryptonemiacese, multitude of forms of, i. 234 



structure of, i. 234 

 Crystal, rock, its transmission of chemical solar rays, i. 65 



absorption of invisible rays by, i. 65 



change of position of the optical axes of the crystals of, by heat, 



i. 73 



Crystallization, relation of polarization of light and heat to crystalliza- 

 tion, i. 70, 71 



axes of symmetry of crystals, i. 71, 72 



change of position of the optical axes of crystals by heat, i. 72 



effect of pressure on the optical axes of crystals, i. 73 



influence on the aggregation of, i. 73, 74 



probable origin of the crystalline form, i. 74 



causes of the variety of forms assumed by matter, i. 74 



deviation of dimorphous crystals from the general law of crystal- 

 lization, i. 75 



proof of the connection between the magnetic forces and crystalline 

 structure, i. 76 



conditions of the position which crystals take with regard to the 



magnetic force, i. 76 



Crystalloids, or crystalline substances, diffusibility of, i. 109 

 Crystals, water an essential element in, i. 107 



alterations in crystals by heat, i. 108 

 Cusconine, structure of, and whence obtained, i. 427 

 Cuthbert's, St., beads, ii. 175 

 Cutaneous diseases caused by fungi, i. 274 

 Cutleria multifida, structure, mode of reproduction, and habitat of, 



i. 248 



Cuttle fish, structure of the, ii. 245-247 



Cyanogen, combines with other substances and simple atoms, as if it 

 were a simple element, i. 106 



combination forming it, i. 106 



Cyathea medullaris, used as food in New Zealand, i. 360 

 Cyatheae, structure of, i. 360 

 Cyatheinese, characters of the group, i. 344 



sporangia of, i. 343 



structure and fructification of, i. 360 

 Cycloclypeus, structure and habitat of, ii. 48 



Cyclops quadricornis, structure and mode of reproduction of, ii. 205, 206 

 Cydippe pileus, structure of, ii. 101, 102 



