RECENT MEMOIRS ON FRESHWATER RHIZOPODA. 373 



spicules, through which the water can freely pass to the 

 surface of the globular body." And he points to the seeming 

 vacant interval between the spicular stratum and the surface 

 of the body as an evidence that there is no compact sarcode- 

 mass surrounding the body. 



Having already defended my own views 1 need not even 

 briefly recapitulate; but really, although Professors Hertwig 

 and Schulze seem apparently opposed to my view, I venture 

 to think it is only apparently , and that the views, at any 

 rate, of the latter, as expressed above, admit all I had 

 contended for. The peripheral portion of the body- 

 substance is the same in nature and consistence as that 

 which forms the pseudopodial envelope, and could, I fancy, 

 equally take a share in giving off the possibly lacunar, cer- 

 tainly very delicate and soft, stratum, forming, as it were, 

 a matrix for the spicules. The space immediately exterior 

 to the globular body is usually without spicules, but I query 

 if it is absolutely and everywhere destitute of Schulze's ad- 

 mitted '^ weiche Sarcode." 



The spicules must have taken origin within living matter, 

 and the whole stratum may certainly by degrees in greater 

 age get pushed aloft, by and-by leaving a void region 

 below it. 



As regards points of difference between this form and 

 R. viridis, they strike me as specifically important, apart 

 from the absence in the former of the chlorophyll-granules. 

 It is true that in R. viridis these are sometimes colourless 

 and, as it were, gradually becoming starchy in appearance, 

 but they are mostly present in great abundance and prevent 

 any insight into the interior. In R. pallida the pseudopodia 

 are seemingly granuliferous, and show here and there fusi- 

 form thickenings. In R. viridis they are not granular, but 

 homogeneous. In fact, with black ink it is really not possible 

 to give on paper a correct representation of them ; an ex- 

 tremely fine line of weak gum- water would be more true. 

 Again, they are a great deal longer than Schulze depicts for 

 his R. pallida, and I think amongst the most important and 

 special of the idiosyncrasies evinced by particular rhizopods 

 are those inherent to and shown by the pseudopodia. Again, 

 R. viridis never has shown pulsating vacuoles. Further, I 

 have never noticed its containing any incepted food. Its 

 opacity could act as a hindrance to the perception of such 

 an inner system of radiating " spines " as Schulze describes 

 for R. pallida, but I would by no means say it does not exist. 

 A nucleus cannot be made out in the body-mass of R. viridis 

 in the ordinary state, but the application of carmine solution 



