114 



met at least one form which I am greatly disposed to suspect 

 would belong here, but I know it too slightly as yet to venture 

 to record it. But it strikes me that in the form to which I 

 allude, the outer marginal region is distinctly flexible, giving 

 w^ay to certain circumscribed changes of figure of the rhi- 

 zopod. If so, I can hardly suppose this outer region can be 

 a siliceous skeleton. Nor does it appear to me porous, 

 though showing an evenly and regular dotted appearance 

 through its substance, and giving a passage to exceedingly 

 fine pseud opodia. In this rhizopod I certainly did but con- 

 sider that I had before me a form coming close to Hetero- 

 phrys, but difi"ering in the sharply bounded outer surface of 

 the comparatively rigid marginal region not being mobile 

 nor divided into processes. 



If, however, Greef's interpretation be truly correct, then 

 the nearest relationship of the genus would seemingly be to 

 Clathrulina, which would differ by the very much larger 

 " pores" to the globular " skeleton," and this being supported 

 on a stipes, and in the absence of the " central capsule" pre- 

 sented by Astrodisculus. 



But opposed to Greef's opinion as to the nature of this 

 outer region is the fact he mentions, that not only do the 

 pseudopodia project through it into the water (which they 

 might certainly do through extremely fine pores), but also 

 that the large characteristic red granules (in A. ruber) can 

 pass in and out along the pseudopodia with ease. Now, 

 this being so, it is not readily to be seen how they could 

 do so unless considerably large " pores" existed, which, if 

 present, must readily be seen, but no one of his forms re- 

 veals such. May I then, as yet, venture to suppose that the 

 outer region (as I certainly thought in the Irish form I have 

 in my mind's eye) is but a more dense and more hyaline 

 sharply defined diff'erentiated region of the sarcode body — 

 more dense, I say, than the inner region, but not too dense 

 to allow of the passage of not only the pseudopodia, but of 

 the large granules at any given spot ? 



Of the newly established genus Astrodisculus, Grccf re- 

 cords the following species ; no strict diagnosis of their cha- 

 racters is given, but I venture to abbreviate his general 

 account of them as follows : 



A. minutus (Greef).^ 

 Sarcode of inner body of a greyish-brown colour, en- 

 ' Lop. cit.. t. xxvii, fig. 30, 



