Jf 



26 PROTOPLASMIC THEJ9^ BEFORTET'IS^O' DUJARDIN. 



1835. When speaking of the Rhizopoda, which he thus names 

 for the first time, he says, " On ne pent voir la de veritable 

 tentacules, c'est une substance animale primaire qui s'etend et 

 pousse en quelque sorte, comme des racines." And he speaks 

 of the simplicity of the tissue, calling it a " sorte de mucus 

 doue du mouvement spontane" et de la contractilite " (p. 314). 

 His next mention of the subject is in vols. iv. and v. of the 

 same work. In this paper which treats of certain Rhizopoda, 

 chiefly the Gromia oviforinis, and Miliola and Amcebea, he shows 

 the absence of any investing membrane. He first uses the term 

 sarcode in describing the movements of the Proteus tenax, 

 stating that, before its death, " il se montre entoure de cette 

 matiere diaphane glutineuse que j'appelerai sarcode, et qui 

 exsude a travers le sac membraneux " (p. 354). 



In another lively individual he notices and figures two glo- 

 bular exudations of sarcode, which changed their place during 

 the movements of the animal, and his subsequent descriptions 

 and plates give those movements and bulgings which all who 

 have observed Amoebae and similar organisms, are familiar with. 

 He attributes the movements to an inherent force in the mass 

 of the sarcode, but that it is rather a force of extension than 

 contraction which enables the Ehizopoda to push out these 

 prolongations (359). 



He then enters on a treatise in detail (364) upon the sarcode. 

 " I propose to name thus, what others have called a living jelly, 

 viz., that glutinous substance, diaphanous, insoluble in water, 

 contracting into globular masses, sticking to the dissection 

 needles, and thus capable of being drawn out into thread like 

 mucus, and, finally, which is found in all the inferior animals 

 interposed between the other structural elements " (367). He 

 then describes its contractile movements, and thus accounts for 

 the formation of vacuoles, which had been erroneously taken 

 for stomachs by Ehrenberg. The rest of the memoir is devoted 

 to the description of various flagellate infusoria, and to demon- 

 strating the absence of those organs which had been given to 

 them by Ehrenberg. 



The next in chronological order, viz., 1838, were the views of 

 Schleiden, which are peculiarly interesting as prefiguring the 



