116 Mr. H.J. Carter on the Organization of Infusoria, 



though it still retains great tenacity ; and thus the expansions 

 of the subjacent tissue are seen to burst through it in much the 

 same manner that the end oi' a stream of lead bursts through 

 its pellicle. Finally, when all activity ceases, and the Amwlm 

 becomes stationary (by fixing itself to some neighbouring object 

 through a pedicular prolongation of the pellicula), a new layer of 

 the latter is formed below the old one, and thus the capsule is 

 formed, and the pellicula replaced on the body of the Ammba^ 

 until the latter becomes firmly encysted (PI. V. figs. 6, 8)*. To 

 what part of the body of the Amoeba the pedicular process cor- 

 responds, I am ignorant; but it is interesting to see that in 

 Euglcna, where a similar process takes place, it is the anterior 

 extremity which is next the pedicle (fig. 9). Many freshwater 

 Rhizopoda secrete a testaceous covering, which increases in size 

 with the animal ; but the fleshy part of the body being for the 

 most part free, is of course still covered with pellicula. The 

 pellicula forms the surface-covering of Astasia and Euglenaf, as 

 well as that of all the holo-jjmly-, diplo- and /wowo-ciliated flexible 

 animalcules and zoospores. Here too, probably, the cilia them- 

 selves are also covered with it, though secreted by subjacent 

 organs, analogous perhaps to those which secrete the hairs on the 

 bodies of higher animals, — a supposition that would appear ridi- 

 culous did we not find such a cori-espondence between the vital 

 processes of the highest and lowest developments as to induce us 

 to think the latter are but a repetition of the others on a smaller 

 scale; that is to say, efl'ected by similar agents, of corresponding 

 minuteness, conducted on the same principle. Taking the 

 above view of the pellicula, we must regard it as a structureless 

 product, which hardens after secretion. May we not infer that 

 there is a layer belov\', specially organized for its formation ? 



Dinphane. — By this name I would designate the moving 

 substance on which the pellicula rests (figs. 1-3). Amoaba, 

 whose primary figure is spherical, has the power of changing 

 this into an almost unlimited number of secondary forms, most 

 of which, being attended with root-shaped prolongations, this 

 Infusorium is justly entitled to a place among the Rhizopoda. 



, * After this the numbers alone of the figures will be inserted, as they 

 are continuous throughout the three plates. 



f Although Astasia and Euylena are here mentioned together, it seems 

 that, in classification, one should be on the animal, and the other on the 

 vegetable side of Amaba ; for Astasia possesses a mouth and complicated 

 buccal ap])aratus for biting off and taking in food, while Euylena appears 

 to have no mouth, and to be nourished by endosmosis. The half-deveJoped 

 cilium, too, in Euglena, compared with the strong prehensile organ wliich 

 occurs in Astasia, with many other points which will be mentioned here- 

 after, allies the former as much more to the zoospore or gonidiura of the 

 Algaj, as the reverse does the latter to the higher Infusoria. 



