CRU 



CRY 



Echino-dermaious animals which resem- 

 ble lilies, of which the fossils called stone- 

 lilies and encrinites are examples. The 

 fossil remains called irochi and St. Cuth- 

 herfs beads are separated portions of the 

 earthy framework of encrinites. 



CRITICAL PHILOSOPHY. A term 

 sometimes applied to the metaphysical 

 system of Kant from his famous work 

 entitled "Criticism of Pure Reason." 



CRbCO'NIC ACID {crocus, saffron). 

 An acid derived from carbonic oxide, and 

 named from the saiFron colour of its 

 salts, called croconates. 



CROCUS (/cpoKot). Saffron. An old 

 term applied to oxides and other prepa- 

 rations of the metals, from their saffron 

 colour: thus we have crocus martis, or 

 oxide of iron ; crocus metallorum, or 

 oxide of antimony ; crocus Veneris, or 

 oxide of copper. 



CROP, or CRAW. A sort of prelimi- 

 nary stomach in some birds, formed by 

 an expansion of the oesophagus. Com- 

 pare Gizzard. 



CROP OUT. A technical term, to 

 denote the rising up, or exposure at the 

 surface, of a stratum or series of strata. 



CROSS-STONE. Harmotone, or py- 

 ramidal zeolite, found in mineral veins 

 and agate balls. 



CROTA'LIDiE (crotalus, a rattle- 

 snake). A family of Ophidian reptiles, 

 including the Rattlesnakes and the 

 Vipers, and all the venomous species. 

 They are distinguished from the Colu- 

 beridae principally by the character of the 

 teeth. 



CROTCHET. In Music, a character 

 constituting the fourth part of a semi- 

 breve ; its duration, in slow time, is 

 about one second. 



CROTO'NIC ACID. latrophic acid. 

 A solid, volatile, and highly poisonous 

 acid derived from croton oil, the fat oil 

 of the seeds of Croton iiglium. 



CRU'CIATE {crux, crucis, a cross). A 

 designation of the corolla of cruciferous 

 plants, from the resemblance of the 

 arrangement of the petals to the pieces 

 of a Maltese cross. 



CRU'CIBLE. An earthern vessel in 

 which substances are exposed to high 

 temperatures. The term is derived either 

 from crux, a cross, which the alchemists 

 stamped upon the vessel ; or from crucio, 

 to torture, because the metals were tor- 

 tured in crucibles, in order to convert 

 them into gold. 



CRUCI'FERiE {crux, crucis, a cross, 

 fero, to bear). The Cruciferous tribe of 

 94 



Dicotyledonous plants. Herbaceous plants 

 with leaves alternate ; flowers polype- 

 talous ; sepals 4, deciduous, cruciate, 

 alternating with 4 cruciate petals ; sta- 

 mens 6, hypogynous, tetradynamous ; 

 fruit a siliqua or a silicula. 



CRUST OF THE EARTH. The super- 

 ficial parts of our planet which are acces- 

 sible to observation. 



CRUSTA. A term applied to the brittle 

 crustaceous thallus of lichens; to the 

 bony covering of the crab, the lobster, &c. 



CRUSTA'CEA {crusta, a shell). A 

 class of articulated animals with an ex- 

 terior shell which is generally hard and 

 calcareous, and is cast off periodically, as 

 in the crab, the shrimp, the lobster, &c. 



CRUX. The Cross; a southern con- 

 stellation, situated close to the hinder 

 legs and under the body of Centaurus. 



CRY'OLITE (Kpuop, frost, XiOos, a 

 stone). A mineral consisting of the 

 double hydrofluate of alumina and soda, 

 occurring in gneiss. The term is derived 

 from the property which this mineral 

 presents of fusing readily in the flame of 

 a candle. 



CRYO'PHORUS (jcpuop, cold, ^epw, to 

 bring). An instrument for exhibiting the 

 degree of cold produced by evaporation. 

 The term denotes frost-bearer, and it is 

 well illustrated by the Cryophorus of 

 Wollaston, which consists of two hollow 

 glass balls connected by a bent glass 

 tube, one of them containing water ; the 

 cold is transferred from one ball to the 

 other. 



CRY'PTA (KpuTTTOf, concealed). Glan- 

 dulcB impressce. A term applied to the 

 vesicular receptacles of oil found in the 

 leaves of the orange and of all myrta- 

 ceous plants. 



CRYPTOBRANCHIA'TA (kputtto?, 

 concealed, /Sp«7X(n. gills). A designa- 

 tion of those molluscous and articulate 

 animals, which have no conspicuous 

 gills. 



CRYPTOGA'MIA {Kpvmo?, concealed, 

 ydfxoi, nuptials). A class of plants, in- 

 cluding ferns, mosses, sea-weeds, &c., in 

 which the fructification, or organs of re- 

 production, are concealed. These are 

 also called agamous, acotyledonous, and 

 cellular plants. See Phanerogamia. 



CRYPTO'GRAPHY (kputttop, secret, 

 7pa0to, to write). The art of writing in 

 a secret manner, as in cypher. See 

 Cypher. 



CRYPTONEU'RA (Kpun-TOf, concealed, 

 vevpov, a nerve). A term applied by Ru- 

 dolph! to those radiate animals in which 



