. The illustrated natural history [microform]. Reptiles; Fishes; Mollusks; Natural history; Reptiles; Poissons; Mollusques; Sciences naturelles. m/ RAD I ATA. E C IT I X 0 D 1': R M A T A. Wk now nriive at a vnxt ainl coiuiircln iisivc divisimi of livinj,' licinffs, wliidi liavc w\ joints wliiitt'vor, and no limits, and avc callrd Jfadiiila, In'causo all Micir parts ladiatc t'l'diii a fonnnoii cciitn!. Tlin Htnictiuv is vci'V evident in siuiio of tlase lieinj^'s, Imt in dtiuis tin formation is so exceedingly obscui'o, that it is only by anatonucul iuvcstigatiuii that tlnii real ]iosition is di
. The illustrated natural history [microform]. Reptiles; Fishes; Mollusks; Natural history; Reptiles; Poissons; Mollusques; Sciences naturelles. m/ RAD I ATA. E C IT I X 0 D 1': R M A T A. Wk now nriive at a vnxt ainl coiuiircln iisivc divisimi of livinj,' licinffs, wliidi liavc w\ joints wliiitt'vor, and no limits, and avc callrd Jfadiiila, In'causo all Micir parts ladiatc t'l'diii a fonnnoii cciitn!. Tlin Htnictiuv is vci'V evident in siuiio of tlase lieinj^'s, Imt in dtiuis tin formation is so exceedingly obscui'o, that it is only by anatonucul iuvcstigatiuii that tlnii real ]iosition is discovered. The highest forms in this division have heeii ptatherod tof^'cthor in the class Echiim- dormata. This word si^niilies Urchin-skinned, and is '^iven to the ai;inia!s c()ni|irisiiiL,'it because their skins are nun-e or less furnislied wiiii spines, resendiling' ihose of tiio lud^c- hog. In these animals the radiate form is very plainly shown, some of tliem assuniiii;; .i perfectly star-like shape, of which the conimou star-tishes of our coasts are famihai examples. In some of the Iiadiates, such as the sea-urehin, the whole hody is eiiciustul with a chalky coat, while in othrrs it is as soil and easily torn as if it Mdre composed of j mere structureless gelatine, The mode of walking, or rather creeping, which is practised by tluse lieings, is viiy interesting, and may be cMsily seen by watciiing the proceedings of a common star-lh'i when placed in a vessel of sea-water. At first it will be (juite still, and lie as if dead, 1>ut by degrees the tips of the arms will be seen to curve slightly, and then the creatuif slides forward witliout any perceptiltle means of locomotion. If, however, it be suddciilv taken from the water and reversed, the mystery is at once solved, and the walknu' apparatus is seen to consist of a vast nundier of tiny tentacles, each with a little reuml transparent head, and all moving slowly but continually from side to side, sonidiim â >: lii'
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Keywords: ., bookcentury1800, booksubj, booksubjectfishes, booksubjectmollusks
