KECENT MEMOIRS ON FRESHWATER RHIZOPODA. 353 



the latter, one or two^ rarely more, globular vacuoles, not 

 showing distinct rhythmical pulsations, but still originating 

 and again disappearing. These occur constantly at the pos- 

 terior end. 



Just under the frontal flagellura and from the anterior end 

 of the granular endosarc an irregularly rounded, smoothly 

 bounded, rather strongly refractive body, of about 0*009 

 millimetre in diameter, projects, rendered more striking as 

 it does not appear in direct contact with the ectosarc, but is 

 separated therefrom by a region of clearer, probably more 

 thinly fluid, character. The outer contour of this clear space 

 does not run parallel to the approximately round surface of 

 the dark body, but is drawn out anteriorly into a point, Avhich 

 touches up quite to the base of the flagellum. Whether 

 there were any direct communication of this clear space 

 with the surrounding water — any kind of oral opening — the 

 author could not decide. The dark body seems to lie in a 

 depression of the endosarc, the thin fluid mass probably, 

 indeed, encompassing it all round. In its interior it shows 

 a number of minute, globular, sharply bounded, clear spots, 

 which have the power to alter their positions, the whole 

 body having the power to alter its figure from globular to 

 oval, or bluntly angular. 



It is doubtful whether the peculiar body so described is to 

 be regarded as the whole nucleus or perhaps as nucleolus 

 only. In the first case a nucleolus and nuclear membrane 

 would be wanting; in the latter case the clear mass sur- 

 rounding the dark body, sharply bounded, but not limited by 

 a membrane, would be regarded as nuclear contents. Very 

 striking, then, would be the connection of the anterior pointed 

 end of the outer part of the nucleus with the body-surface 

 of the whole animal and just at the place of the insertion of 

 the flagellum. 



The very few examples of this remarkable form seen by 

 the author were rather mobile, and soon began, after some 

 irregular turnings, to move straight away as described, with 

 manifold alterations of form and position, the pseudopodia 

 the Avhile projected and retracted. 



The author did not observe the act of inception of food, 

 though he had several times seen the ejection of fecal 

 matter and from the posterior end, without, however, per- 

 ceiving any marked anal region ; nor did he notice any kind 

 of reproductive process. 



