S66 W. ARCHER. 



shows some non-prominent contractile vacuoles, pseudopodia 

 — what applies to A. spinifera holds good here. The authors 

 regard the colourless or coloured rounded corpuscles met with 

 in the ectosarc as due to the gradual breaking up of the food 

 during the digestive process, and they record indeed having 

 traced the transformation of such into these corpuscles ; at first 

 during the breaking up of the incepted bodies they supposed 

 they had encountered a more or less advanced process of 

 self-fission, but they afterwards found this was an error. 

 They regard indeed the chlorophyll-granules, when present, 

 just like these colourless corpuscles, as due to the inception 

 and breaking up of algal organisms, and go so far as to 

 suggest that in all cases the green granules in Heliozoa owe 

 their origin to algse incepted from without. In this view I 

 would myself as yet not at all feel inclined to coincide ; in such 

 forms as yf. turfacea, Raphidiophrys viridis, the intra-peri- 

 pheral layer of chlorophyll-granules appears so comparatively 

 constantly and seemingly characteristically ; even when these 

 forms are found colourless these same granules seem still to 

 be there, if I mistake not, but deprived of colour— if I might 

 venture to suggest, somewhat starchy in appearance. It is, 

 no doubt, possible (perhaps not unfrequent) that such rhizo- 

 pods may incept numerous green algse and their zoospores, 

 &c. ; such examples would offer a green apjjearance until 

 digestion had set in, but this would be merely exceptional 

 and altogether different from the aspect of the habitually 

 green forms. 



This seems a perfectly distinct species ; it has not, however, 

 met my own observation. 



Acanthocystis flava, Greeff. (Pig. T.) 



To this genus Greeff adds another seemingly well-marked 

 species under the above name.^ It is characterised by its 

 yellowish-brown colour, showing in the interior some red or 

 dark brown granules, as well as some of larger size colourless. 

 It possesses a median globular, apparently hyaline central 

 body, doubtless nucleus, designated '^central capsule " by the 

 author. The radial spines are scarcely a third of the body- 

 diameter, comparatively broad at the basis, gradually 

 attenuated upwards and acute at apex, and are seated on 

 the surface of the body by the usual basal plates. The 

 pseudopodia appear to be about one and a half times the 

 length of the body-diameter. 



1 Greeff, loc. cit., p. 17, t. i, f. 5. 



