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Observations on the Digestive Organs of the Infusoria. 

 By J. Meyen. 



All naturalists are aware that Gleichen, in 1781, tried to 

 make certain infusoria eat carmine, and observed next day 

 that they had several large red granules in the interior of their 

 bodies. He thence concluded that they had swallowed the 

 colouring matter. He likewise noticed that these coloured 

 granules afterwards made their escape by another opening. 

 Gleichen has figured these red granules very accurately ; each 

 of them is in the centre of a particular circle, the nature of 

 which he does not explain. At a later period M. Ehrenbei-g 

 made the same remark, and he thence concludes that the in- 

 fusoria have several stomachs, which in one section are des- 

 titute of an intestinal canal, while in others they not only 

 possess canals by which they communicate with each other, 

 but lateral appendages besides, which terminate in a coecum. 

 In consequence of these discoveries, these infusoria were de- 

 signated by the name of Polygastric Animals. M. Ehrenberg 

 believes that he has proved that their stomachs are filled one 

 after another, and he has figured, more or less completely, the 

 intestines which form the communication between the different 

 stomachs. 



Many observers have already questioned these assertions 

 of M. Ehrenberg ;* for my own part I never admitted them, 

 because, in the first place, I never could see the intestines 

 which form the communication between the stomachs, and 

 likewise because I have observed, many years since, that these 

 supposed stomachs were moving in the interior of the body of 

 many species with great rapidity, in the same manner as the 

 granules which circulate in the joints of the chara. I have 

 often seen Vorticelles with nine or ten large globules of indigo 

 in the belly, Avhich always moved round a centre, and thus 

 shewed, in the most evident manner, that they could not have 

 a communicating canal between the stomachs provided with 

 an anal orifice and an extremity directed to the mouth. 



* iSoe the Memoir of M. Dujiirdin on tlii« sulycct, in tlic lOtli volume of 

 the Annalcs des Sciences Niiturellcs. 



