S68 Dr, G. C. Wallich on an undescribed Indigenous Amoeba. 



to is of the nature of a nucleus. In appreciable characters, both 

 as to colour, form, and size, the component granules are identical 

 with those seen in the true nucleus. But the analogy is well 

 nigh confirmed from the circumstance that, at a still later period, 

 when evaporation of the water had gone on to a greater extent, 

 the entire granular mass referred to became segregated, as if by 

 a process of segmentation, into numerous distinct nuclei, amongst 

 which the true nucleus was not recognizable as a separate or 

 diflferent structure. These multiple nuclei, varying in number 

 from five to about a dozen, were contained in no separate cavity 

 or cavities, but occupied the position previously occupied by the 

 single large granular mass. In the specimens exhibiting this 

 structure, the animal seemed inclined to assume an encysted 

 form, motion being almost totally suspended, and the short 

 conical pseudopodia projected from all parts of the surface except 

 the villous area, being withdrawn and re-extended with extreme 

 slowness, and only at long intervals (Plate IX. fig. 5). After 

 a time (whether from the pressure of the glass cover or other- 

 wise, I am as yet unable to determine), these multiple nuclei 

 were extruded, one by one, in the vicinity of the villous area. 

 During extrusion, and for several minutes subsequently, they 

 retained their spherical mulberry-like form. They then, one 

 after the other, fell asunder as it were, — the granular disruption 

 seeming to commence at a single central point, and afterwards to 

 extend equally on all sides. The granules, when released, formed 

 a delicate cloud, each grannie maintaining a tremulous and 

 apparently molecular movement for a few seconds, and ulti- 

 mately assuming a condition of perfect rest. At fig. 5« I have 

 shown one of these nuclear masses as seen when first extruded. 

 In a single example, occurring in the material originally pro- 

 cured, a very distinct membranous capsule was observable (fig. 6). 

 This had all the appearance of being true ectosarc, inasmuch as 

 it not only closely invested the body, but the boundaries of the 

 villous area. I have already stated in my previous paper that 

 acid and alkaline reagents failed to render evident any such 

 membrane as is alluded to by Auerbach and Schneider. Ke- 

 peated attempts with these reagents have since been made by 

 me to bring the membrane into view, but without success. In 

 the single specimen now under notice, all movement of the body 

 had entirely ceased, and it appeared to be strictly encysted. But 

 there still remained a slow cyclosis of the granular particles ; so 

 that life was not extinct. It is just possible, therefore, that the 

 membranous capsule may not have constituted an integral por- 

 tion of the Amoeba in question, but that the latter may have 

 accidentally insinuated itself into the efiete cell of some other 

 animal. It is a significant fact, however, that the membrane 



