36 Mr. H. J. Carter on Amoeba princeps 



consideration, while, for a short time, our attention is directed 

 to the peculiar function of the sarcode and its motion in con- 

 nexion with that of the diaphane, and also to the theories that 

 have been adduced to account for the wonderful phenomena which 

 they present. 



Of the "peculiar and particular function" of the sarcode 

 there can be no doubt, viz. that of digestion ; for we may watch 

 this, from the inception of the food, through its being broken 

 down by the solvent process, to the ejection of the refuse. But, 

 by analogy, it would appear to have another function ; else why 

 should its rotatory motion go on unceasingly, like that of the 

 protoplasm of the plant-cell, to wit, in Nitella, where it is not 

 called upon to exercise the function of digestion ? The other 

 function, then, that I would attribute to the sarcode is that of 

 aeration or respii-ation. In JEithalimn, the rapidity with which 

 the sarcode and its contents continually rush round the interior 

 of the massive portions, as well as through the minutest arbor- 

 escent branches, is astonishing; nor does it cease for a moment, 

 under ordinary circumstances, until all is prepared for the last 

 change of form, viz. that for fructification, when life is about to 

 become extinct from everything but the bits of protoplasm wrapt 

 up in the little sporidia, for the future perpetuation of the spe- 

 cies. Such is also the case with A. princeps, although there are 

 certain short intervals of cessation which take place, ex. gr. when 

 this Rhizopod is much disturbed ; and it is worthy of notice 

 that the movement in the sarcode at these times does not com- 

 mence until the diaphane has also commenced to transform the 

 Amceba. 



As regards the composition of the diaphane and sarcode. Max 

 Schultze some time ago put forward the theory that they were 

 composed of protoplasmic nucleated cells, which, coalescing on 

 the surface, formed the transparent diaphane, but gradually re- 

 tained more of their cellular individuality inwardly, where they 

 formed the sarcode; so that, in short, the diaphane and sarcode 

 thus pass into each other *. 



On the other hand, Reichert, whose observations here are 

 confined to the Foraminiferous Rhizopods, is of opinion that the 

 diaphane or pseudopodia are composed of extremely minute fila- 

 ments which do not coalesce, but, from their plasticity and 

 transparency, adhere to each other with such mutual adaptation 

 that their individual forms cannot be distinguished under cir- 

 cumstances of combination, while they always retain their primi- 

 tive form under separation f. 



* Ann. Nat. Hist. vol. vii. p. 318 (1861) ; translated from Wiegmann's 

 Archiv, 18G0, p. 28?. 



t Ann. Nat. Hist. vol. x. p, 403 et seq. (1862); translated from the 

 • Monatsbericht der Akad. der Wissenschaften zu Berlin,' 1862, p. 406. 



