CARPENTER OH CHB A BBAftTG CM EOT "l THE HI! 1ZOPODA. tOS 



envelope, are presented by the genera %r i chad Urn, ,?, 'Blagidphryty 

 and Muylyphu, which are associated with it by MM. Claparede and 



Lachmann in the family Aeti nophryna. \)\\\ they seem to me — 80 

 far as I can judge by the published desci -ipt ions of these animals, 



which I have not myself bad the opportunity of examining in their 



living state* — not less unmistakcaldy exhibited In the A<<intho- 

 ■metrina and the Polycystina, which may be regarded as higher OF 

 more specialized forms of the same type. The radiating psomlopodia 

 of Acanthometra correspond precisely in all their character.- with 

 those of Actinophrys ; having the same rod-like tapering form, the 

 same regularly radiating arrangement, the same mutual isolation, and 

 the same slow movement of particles along their surface: some of 

 them, however, are enclosed in tubular siliceous sheaths, which appear 

 to be secreted from their surface ; and the union of the expanded 

 bases of these sheaths forms a sort of framework, that supports the 

 protoplasmic substance of the body. In this substance the differen- 

 tiation of endosarc and cctosarc has obviously proceeded further than 

 in Actinophrys ; and the endosarc contains a number of cell-like 

 bodies resembling those of the Thalassicollw. The animal of the -Poly- 

 cystma seems to correspond with Acanthometra in all essential par- 

 ticulars, the difference being only in the disposition of the siliceous 

 envelope ; and that of the Thalassicollina appeal's to be only a more 

 composite aggregation of the like structural components. For details 

 of the evidence of the relations of the last-named groups to each other 

 and to the preceding, I must refer to the memoir of Prof. Midler 

 already cited ; and his designation Kadiolaiua 1 adopt as that of the 

 group to which he applied it, with the addition of the family Act'rao- 

 phryna. That family, as I have endeavoured to show, really supplies 

 the typical form of the Order; the naked Actinophrys bearing the 

 same relation to the testaceous Polycystina (i'ov example) that the 

 naked Amoeba does to the testaceous Arcclla and DiJJlugia, or the 

 naked Lieberkuhnia to the testaceous Gromiila and Foraminifera. 



III. — Erom the Actinophryna and the other Khizopods of the 

 order Radiolaria, the Amcebina seem to me to be very definitely dis- 

 tinguished by the more complete differentiation of the containing 

 and the contained portion of their sarcode-bodies. and by the entire 

 difference (as regards, at least, the typical forms of each group) in 

 the character of their pseudopodial extensions. The distinction be- 

 tween the ectosarc and the endosarc is far more clearly marked in 

 Amoeba than in Actinophrys ; the latter being much more fluid, 

 whilst the consistence of the former is much tinner. It is through 

 the endosarc alone that those coloured and granular particles are 

 1 



* I am not aware that Acanllovietrr? have yet h« en soon uji.ni our roasts. Then- 

 seem, however, to abound in the North Sea, and should therefore, he looked for u|m.ii 

 our eastern shores, especially when the wind blows towards tliein. 'I lie Acautho- 

 virfra rchuuhh's, whieh abounds on ihe we-teni coast of .Norway, is discernible by 

 the nahed eyes a erimson led i:oiut. 



VOL. I. — N. H. H. 3 



