CRYOUTK. 



CKYSTALLOQKAl'llY. 



i several exsmples of the CVtufoora of thu forma- 

 It oontela* specie* of Limuliu, and alo of a genus 1 

 aWed to Ox recent rniu ^ <<-. 



la UM Chalk, specimen* of CmHaeta ara found fomenting both 

 the lobster and the orab. The following lUt of specie* ia given by 

 Tennant in hi* ' Brituh Fosaila :' -.U'ocw JWAW, X. lo*yimo*<u, ' 

 StOHwinmi, Oritkrya Btttri, Paaunt Patyatii, ScyUani tlanlMii. 



In the Tertiary bed* UM remains of Ourtocra are not very numerous, 

 but their form* are many of them identical with thoie now existing. 

 Many form* remain yet to be discovered, especially among the minute 

 TtoaM*fnMu [CYTHKKil of which only a few hare yet been described. 



(Bell, Uuiory of tiu Brilitk Stalk-Eytd Onttacta; Owen, Lecture* 

 * Otmpfratirt Anatomy ; K. Jones, Outline* of Animal Kingdom; 

 OftUfudia of Anatomy and Pkynology, article Cruttacta ; Stance 

 BaU, in AnnaU of .\atural Uulory ; Milne- Ed wards, Uittoire Natu- 

 nlle da Cnutaeia ; Rathke, L'nltrtufltungen iikcr die BUdung und 

 tntwidHlumff dt Flutt-Krtbm ; J. V. Thompson, HeiamorplutK* of 

 Cnutacta; Rupert Jonea, Monograpk of Ike Enlomottraca m Ike 

 Cretoftout Formation* of England Pal. Soc. ; W. King, Monograph of 

 Permian Pauilt Pal. Soc. ; Baird, Ilitturf of Brititk Bntomottraea 

 Ray Soo. ; Burmeister, Tke Organisation of Trilebittt Ray Soc.) 



CKYOI.ITK, a specie* of Mineral, a fluate of soda and alumina. 

 It U of a white colour, or reddiah, or yellowish-brown, and its streak 

 ii white. It occur* in crystalline masses, but its primary form hag 

 not been observed ; its cleavage U parallel to the terminal and lateral 

 plane* of a rectangular prism. It* specific gravity is from 2'94 to 

 rMS. It is not so hard as fluor-spar, U translucent, and by immer- 

 sion in water becomes transparent It fuses by the blow-pipe into a 

 transparent globule, which becomes opaque on cooling. 



It Is found at Arkul-nurd, in West Greenland. According to the 

 analysis of Vauquelin it consist* of 



Fluoric Acid and Water 



Soda . 



Alumina . . . 



47 

 32 

 21 



100 



CRYPTOCE'PHALUS (Geoffrey), a genus of Coleopterous Insects 

 of the section Cyfiica and family Ckrytoaulida. It ia known by the 

 antenna? being filiform, nearly u long as the body ; palpi with the 

 joint* nearly of equal thickness ; bead deeply inserted into the thorax, 

 mall and vertical ; thorax nearly as broad as the elytra : body short 

 and cylindrical. 



Upward* of twenty specie* of this genus are found in this country. 

 The most abundant specie* is Cryptocepkalu* ttrieeut. This little 

 bestls i* of a brilliant golden-green colour, and about a quarter of an 

 inch in length ; it is found during the month of July in the flowers of 

 the Hirracium and similar plant*. 



Cryptottpltaiut Litfola is about the same size as the last, and is 

 found on oak-trees, hasels, Ac. ; it is black and glossy ; the elytra are 

 red, and have an oblong dash in the middle, and the suture and outer 

 margin black. 



CRYPTOCOSCHUS, a name given by some toologists to those 

 MltfUm whose shelly plate* are entirely hidden by the investing 

 bocder. [CmrrosiDJLj 



CKYPTODIBKAXCHI ATA, De Blainville's name for the Cepha- 

 lopodous ifoUutca. [CEPHALOPODA.] 



CRYPTOOA'MIA, the twenty-fourth class of the Linnican System 

 of Plant*. It include* all those genera the flowers of which are either 

 altogether absent, or formed upon a plan different from that of ordi- 

 nary plant*. Fern*, Mouses, Lichens, A Iga, Fungi, with their immediate 

 allies, form UM class, which i* the same a* the Aaotyledon* of Jussieu 

 and UM Ctiluiara of De Candolle. It is often employed to distinguish 

 UM Flowerless from the Flowering Plant*, which are thence called 

 fnmntrtfmmif. [LICHEXI; LTOOFODIACI.M ; Am*; Fvsoi ; DIATO- 

 ucu; Aooocm; DEHMIPE.K.] 

 ITK. [CMUCM.] 



rrCTBAOXDJL] 



< liyiT<)THAOC8(Herbst), a genus of Coleopterous Insect* of 

 the family Bnyida. They are minute beetle*, which are found in 

 fungi and ia flower*, and some of the species are common in damp 



The CrffiojAayi are seldom more than an eighth of an inch in 

 length, generally of a pale brown colour, and more or less pubescent 

 They have UM antenna- rather thick and 11 -jointed ; the basal joint 

 U thicker than the seven following, and the three apical joint* form 

 an elongated knob ; the terminal joint is somewhat conical, and the 

 two preceding joint* an cup shaped ; the haul is nearly triangular, 

 inserted into the thorax a* far back a* the eye* ; the thorax linearly 

 square, and the lateral margin* are more or less denticulated ; they 

 usually exhibit an obtu** tooth-like proces* in the middle ; the elytra 

 ara elongate ; UM (id** an generally straight and parallel, or nearly 

 so, and the apex i* rounded. 



About sixteen sped** have been found in this country. Cryptopha- 

 *l*mt i* sometimes abundant ia puff-ball*, and probably 



CBTPTOPROCTA. [VIVMBID*.] 



CBYPTORHY'.VCHIDES (Hch.mherr), a family of Coleopterou* 

 Insect* btlonging to the section MjnwAopAoro , the species of which 



are chiefly dirtingiilihH by their possessing a groove in the chest into 

 which the rostrum U received when at rest 



This family contains upwards of twenty genera, of which the genus 

 Cryptorhyntkut may be considered a* the type. The characters of 

 this genus are : Antenna: 12-jointed, short, funiculus 7 -jointed, the 

 first joint rather longer than the rest ; club oval or oblong oval ; 

 rostrum moderate, rather arched ; thorax often broader than long, 

 narrower towards the apex, and furnished with tuft* on the anterior 

 part ; elytra somewhat ovate, covering the abdomen ; scutellum dis- 

 tinct ; legs moderate, femora often armed with a spine beneath. 



Of this genus upwards of ninety specie* are known, only one of 

 which inhabits England, Cryptorhynchu* Lapathi. This beetle is less 

 than half an inch in length, and of a dull brownish-black colour . (),. 

 thorax is whiti&h at the side*, and is furnished on the upper part with 

 five black tufts two on the anterior part near the eyes, and three in 

 a line a little behind these, one in the middle of the thorax, and one 

 on each side ; the elytra are brown-white at the base, and white at 

 the apex, and are studded with numerous black tubercles. 



C. Lapathi is found on willows, and is sometimes tolerably abun- 

 dant in osier-beds in the south of England : when touched, like most 

 of its tribe, it contract* it* legs and falls to the ground. 



CRYPTOSTOMA. [CHISMOBBANCHIATA.] 



CRYPTURUS. [TETBAONlBJt] 



CRYSTALLINE LENS. [Kvi.] 



CRYSTALLO'ORAPH Y, or the doctrine of the relations of crystal- 

 line forms, is in strictness an application cf solid geometry ; but it M 

 practically allied to Mineralogy, and may also be regarded as a sub- 

 sidiary department of that science. 



Minerals occur very generally in the state of crystals, that is, in 

 certain definite and symmetrical forms, and these are regarded a* 

 crystals whether they are transparent or opaque. 



A solid figure, of the shape of a common die used in games of 

 chance, frequently occurs among minerals, and U then termed a Cube 

 or Cubic Crystal. 



If the corners of this cube were to be cut off so as to take away 

 equal portions of the three adjacent edges, a new figure would be 

 produced which is aaid to be derived from the cube. 



If the edges were to be all cut off so as to produce new surfaces, 

 making equal angles with the adjacent sides of the cube, another 

 derived form would result In these cases the cube would be deemed 

 the primary form, and the derived figures secondary forms of the 

 cube. 



Minerals are very generally known by their primary forms ; but as 

 these are of different kinds, and as natural crystals are very generally 

 found in secondary forms, from which the primary is to be inferred, 

 a knowledge of the exact relations of the primary and secondary 

 forms U requisite to enable the mineralogist to determine the primary 

 from the secondary, and hence to arrive at a knowledge of the mineral 

 to which any given crystal belongs. 



Our subject may therefore be considered under three heads, 

 namely : 



1. Primary Forms. 



2. Secondary Forms. 



3. The Laws of Derivation, or the mutual relations of the secondary 

 and primary. 



We must however premise a few definitions. 



What we hare called the comers of the cube will be termed its 

 Solid Angles, and so of the corners or points of all other figures. 



A solid angle, or edge cut off so as to produce a new surface, or 

 Plane as it is termed, is said to be truncated. 



The series of forms resulting from each of the primary forms con- 

 stitutes a peculiar System of Crystallisation ; there are consequently 

 a* many different systems a* there are different kinds of primary 

 forms. 



A Prism U a solid figure, having any number of sides with parallel 

 edges, and its two ends parallel. 



A Right Prism is one which stands upright when placed on a table; 

 if it overhangs the base hi the direction of an edge or diagonal it is 

 termed oblique, and if an oblique prism is again oblique in the direc- 

 tion of a second edge or diagonal it is doubly oblique. The bases of 

 doubly oblique prisms are Xisually oblique-angled parallelograms. 



The edges of the sides, and the side planes of a prism, ara termed 

 lateral, and those of the ends terminal edges and planes. 



1. Primary Forma 



These are in some degree arbitrarily assumed, as it appears from 

 the three following figures, showing the relation between the cubes 

 and angular octahedron. 



Pig.lut, Cube. 



Pig. 2, a Cube, with its solid angles truncated. 



Pig. 3, an 8-sided figure or octahedron, which is produced when the 

 solid angles are so deeply truncated as to obliterate all the faces of 

 the cube. 



Now it is, mathematically speaking, indifferent whether we take 

 .he cube or the octahedron as the primary form of all the derived 

 Igures of this system of crystallisation ; for it may be readily per- 

 ceived, from an attentive comparison of the following figures, that new 

 >lnnes which might be produced on the octahedron by the truncation 

 of its solid angles would correspond in position with the faces of the 



