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Show 10 ON CLASSIFIC.A'riO~. is indicated in the table as the 1-tnr.z:;oroDA. I have put a query against it, as I shall have to retl~rn. to it as another of those respecting whieh our knowlcc~go IS 1ncomp~etc. And at this mmnent I n1erely direct attention to the saJwnt and clmracteristic features of the whole group (Fig. 2). Fig. 2. Fig. 2.-A, B, Free and <'ncysted conditions of an Amcaba (after AuerLach ) ; K, a Foraminifer (Rotcdia) with extended pseudopodia; D, its shell in section (after Sr,hulze). It seems difficult to imagine a stage of organization lower than that of G1·egarinida, and yet 1nany of the lUtizopoda arc still simpler. Nor is there any group of the auinutl kingdom which more admirably illustrates a very well-founded doctrine, anu one which was often advocated by II untor himself, that life is the cause and not the consequence of organization; for, in these lowest forms of animal life, there is absolutely nothing worthy of tho name of organization to bo discovered by theinicroscopist, though as~isted by the beautiful in. trun1ents that are now constructed. In the substance of Inany of these creatures, nothing is to be discerned but a n1ass of jelly, which 1night be represented by a little particle of thin glue. Not that it corre- 'HEGARINIDA, HIIIZOPODA, Sl'ON •JuA, A 'D INF , OHIA. 11 sponds with the latter in compo.'ition, bnt it has that texture and sort of a 'P d; it is strneturelcs._ and organic '::-;, and without definitely formed part.'. N c vcrth 1 ... , ', it pos.' s 'CS all the ssentinl propc•rties and characters of vitality; it i, produ • d fron1 a body like itself; it iH eapable of a~siiuilating nouri 'hInent, and of exerti11g moymnents. Nay, Iuon~ it ran procln <' a shell; a struetnn~, in n1any ca~es, of extraordi11ary cmnplexity and most singular beauty (Fig. 2, D). That this partido of j lly i~ {'npal>l<• of combinino· physical forces in such a nuu1ner a to give.. rise to thos xqni -·ito and nJn1o t Inathonuttically-arrangod strnctnros-boing it ·elf ·tructurele s and without ponnnncnt distinction or separation of parts--is, to Iny n1ind, a fact of the profoundest 'ignificanc . Though a Hhizopod is not pernuu1ently organized, how ver, it can hardly be said to be devoid of organs; for the name of the group i derived frmn the po-wer whieh these nnilnals pos es of throwing out processes of theh· ·ub ·tanee, which are ·ailed "pseudopodia," and are smnotime~ very slender and of great length (Fig. 2, E), sometimes broad and lobe-like (Fig. 2, A.). These processes may ilow into one another, so as to fonn a network, and they nuty, commonly, be thrust out fi·01n any part of the body and retracted into it a o·ain. If yon watch one of these auin1als alive, you ~co it thru.'ting out, first one and then another of its pseudopodia, exhibiting changes of form c01npnrable to those which the colourles · corpn ·des of the human blood present. The 1novcment~ of the ·e lthizopods are quite of the .·anw character, only they are nn1eh mor · extensive and e1l'cct locomotion. 'fhe eroatnr' alHo feed 01 it ·elf by In ans of its pseudopodin, whieh attach thmnselvc · to nutritive partieles, and then draw thmn into the substance of tho bocly. There is neither ingestive nor egestivc aperture, neith r SJH •iul Inotor nor prehensile organs, l>nt tlw pseudopodia perfonn en ~h function as it HWY be r quirocl. But here, again, we labour under an impPriection of knowledge·. For, although it i~ quite certain that th Rhizopo(lc~ may 1nul6ply by division of their ·ubRtance-in a \Hty somewhat mwlogou · to ilmt which I cl tailecl wheu ~1Jeakiug uf tlw Gregarinida-y t, as in tlwt. Cft.'C', we have 110 l·uuwk·dge of nuy true ·cxnal pro'<\-;·. H |