C R 



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family Reptilia. It is covered with 

 very hard scales, which can be 

 pierced with great difficulty, 

 except under the belly. It has 

 four feet, and a tail, with five toes 

 on each of the fore, and four toes 

 on each of the hind feet, of which 

 only the three internal ones on 

 each foot are armed with nails. It 

 has a wide throat, with several 

 rows of teeth. The fossil remains 

 of crocodiles are common and abun- 

 dant. Crocodiles are omnivorous. 

 The living species of the crocodile 

 family are twelve, one Gavial, 

 three Alligators, and eight true 

 Crocodiles. Crocodiles, it is said, 

 continue to grow throughout the 

 whole of their existence, and 

 Buckland states their increase to 

 be no less than four hundred times 

 their original bulk, between the 

 period at which they leave the egg 

 and their full maturity. Crocodiles 

 are furnished with a frequent suc- 

 cession of teeth, in order to 

 maintain a duly proportioned 

 supply during every period of their 

 life. The vertebrae of the neck 

 rest on each other through the 

 medium of small false ribs, whereby 

 all lateral motion is rendered 

 difficult, and the crocodile is unable 

 to deviate suddenly from his course ; 

 this renders escape from them 

 facile, by either running round 

 them, or pursuing a zigzag course. 

 The eggs of the crocodile are as 

 large as those of the goose. They 

 inhabit fresh water, but they 

 cannot swallow their food under 

 water. The remains of crocodiles 

 occur in all the secondary for- 

 mations of England, from the lias 

 to the chalk inclusive, as well as 

 in the tertiary formations. The 

 fossil species are numerous, differ- 

 ing greatly both from each other, 

 and from existing species. 

 CHOP-OUT. A. term used by miners to 

 express the rising up at the 

 surface of one or more strata. A 



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stratum rising to the surface from 

 beneath another stratum is said to 

 crop out. Beds are said to crop- 

 out when they make their appear- 

 ance on the surface from beneath 

 others. 



CROSS-STONE. Called also Staurolite, 

 and Harmotome ; it is the Para- 

 tomer Kuphonspath of Mohs, and 

 the Kreutzstein of Werner. Colours 

 white and grey ; occasionally it is 

 found with a reddish and yellowish 

 cast. It is composed of 47 parts 

 silica, 21 baryta, 15 alumina, 

 0'88 potash, O'lO lime, 15 water. 

 It occurs in small quadrangular 

 prisms terminated by four rhombic 

 planes, crossing each other. The 

 surface of the smaller lateral planes 

 is doubly plumosely streaked. It 

 is found in galena veins and agate 

 balls in the mines of Strontian, in 

 Argyleshire, and in other parts of 

 Scotland ; also at Andreasburg, in 

 the Hartz, and in Norway. 



CEOWS'NEST. The common name 

 given to certain fossil cycadeous 

 plants of the genus Mantellia, from 

 an idea that they were formerly 

 built by crows in the fossil trees, 

 which have become silicified. The 

 largest specimens are about two 

 feet high and three feet in circum- 

 ference. 



CEOWSTONE. A hard argillaceous 

 rock, sometimes found forming the 

 floor of the coal-beds : it may be 

 considered to be a highly indurated 

 variety of clunch. 



CEOY'LSTONE. Crystallized cauk. In 

 this the crystals are small. 



CEUCI'FEBOUS. (from crux and fero, 

 Lat.) The name given to a large 

 order of plants, whose petals, four 

 in number, are so arranged as to 

 resemble a cross. The radish, 

 cabbage, stock, &c., are cruciferous 

 plants. 



CEU'CIFOEM. (from crux and forma, 

 Lat.) Cross-shaped; in the form 

 of a cross. In botany, polypetalous 

 flowers are so called, when the 



