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Show 418 INFUSOD.IA.. CLASS V. INFUSORIA. 1 . lly close the catalogue of the animal king. Natura 1sts usua b · · 'bl . b . extremely minute as to e lnVISl e to dom wtth ewgs so · d · d d which have only been d1scovere smce the nake eye, an . . . . f th microscope has unvetled to us, a! 1t were, the 1nventwn ° e · b d f h ld M t of them nresent a gelatmous o y o t e a new wor · os 1 . • • • d b dl h 1. .t and for these, this 1s un ou te y t e g.r eate. st s1bm p IClt hY ' have placed among the I nfusor1·a , an·i· Sltuatwn; ut au ors . . h l tl ch more comphcated, and wh1c on y re· mals apparen y mu . . l' h h . th 1·r minuteness and the dwelhng m wnc semble t em 1n e ' they are usually found. · . ''fhev w1• 1 1 cons t'tute our first order, though we must stlll 1 • • • • . . " h d bts relative to their orgamzat10n which are lDSISt upon t e ou not yet dissipated( 1) · f tl' work does not require me to enter into the endless (1) N.B. As the nature~ u.s 'nute beings and as I can say nothing con· details concerning these mfinbJtely mt.' I can o~ly refer the reader to the work . h f: m my own o serva 10ns, . cernmg t em ro . . t'tl d "Essai d'une Classification des Ammaux of M. Bory de Samt Vmcent, en 1 e f the !n· Microscopiqude:'•" exptra~te1d8f2:r~:~~~:~~~:: ~~~~::n~~:~ea:eo~~~:;\:to eighty· eye. M6tho 1que, :ms, ' two genera. ROTIFERA. 419 ORDER I. ROTIFERA. The Rotifera, as above stated, are distinguished by a greater degree of complication. Their body is oval and gelatinous; we can distinguish in it a mouth, a stomach, an intestine, and an anus near the first. It most commonly terminates posteriorly in a tail that is variously constructed, and anteriorly it bears a singular organ, variously lobate, with denticulated edges, and of which the denticulations vibrate successiveiy in such a manner as to give the organ itself the appearance of one or more dentated and revolving wheels. One or two prominences on the neck have even appeared to some observers to be furnished with eyes. This revolving organ does not serve to direct their aliment to the mouth ; it may be supposed to have some connection with the function of respiration(!). In FuRCULA RIA, Lam. The tiody is unarmed; the tail is composed of articulations which enter one into the other, and is terminated by two threads. It is on one of these-the .Furcula?·ia or Rotifere dea toita-that Spallanzani performed his famous experiments. Covered with dust in the spouts on the roofs of houses it becomes desiccated, and after remaining in that state for several weeks reacquires life and motion on being humected with a little water. . The TRIOHOCERo.&, Lam., appear to me to differ from the Furcu- (1) For the organization of these animals, see the Memoir of M. Dutrochet, Ann. du Mus. XIX, p. 355. |
