CHAITKK XL. 



CHKMKAI. ( oMl'o.SiTlU.N uL-- TTTK PELT, ^fEMHKAXE 



OF ^:I•M^'('KTEs. 



^ 225.— Cellulose. 



TnK (luestion as to tlio chemical composition c.f the sulistjince 

 foustitutiiig the cell membrane of fungi, cuuKl not be a^rit^ited 

 until some information had been gleaned in connection with the 

 an,it^)mical structure of these organisms. This condition was 

 still uufullilled at the time (iSii) when H. Hka. (»x.\oT (IF) 

 subjected cerfciin edible fungi to lixiviation, and applied the 

 Maine fongine to the residue obtiined in this manner. Certainly 

 this subsuiuce, the name of which was afterwards Latinised to 

 fungine, was not a uniforiu bo<ly ; nor does the circumstmce 

 that it was then new, justify the jvssumption that Hmcounot 

 was the first to piepare the cell membi-ane of fungi in a pui-e 

 suite. During the tifties, Paven subjected various fun-'i to 

 hxiviation with ether, alcohol, alkalis, and acids, and made 

 ultnnate analyses of the residues. In this n.anner he obtained 

 bgures which fairly corresponded to the formula ( V.H,„0.. Being 

 unaware of the iunuen.-e number of isomeric "substmces all 

 possessing this elementiiry formula, he deduced from his data 

 the occurrence of pure cellulose in the fungi, and denied the 

 existence of the alleged fungine. The s^ime conclusions were 

 foruuMl in succession by .Soiilossuekuku and D(KITiX(: (l.),as also 

 l)y Fkomiikuq— whose researches were reported by Mildeu (IV ) 

 — ami by A. Kaiskk (I.) in iS6:r. " 



This hypothesis of the i.lentitv of the substance composin.' 

 the cell membrane of fungi on the one hand, and that of higher 

 l)lants on the other, was ba.sed more on prejudice thaif on 

 the results of analysis, and necess;irilv fell to the groun.l on 

 the .hscovery of vari..us reagents giving peculi;u- and distinctive 

 reactions with true cellulose : for iust^mce, ammoniacal copper 

 oxide, whuh was introduced bv E. ScHWEiZEit (I.) in iSs" and 

 <lissolves pure cellulose without leaving anv residue';" zinc 

 lodochloride, which was recommemUvl bv C. N.i;uKi.i (VI 1.) and 

 H vox Mom, (I.), and gives a violet "coloration ; and finally 

 io.losulphuric acid, which gives a blue colorath.n and w.-is fir^t 

 employed l)y Schleideii. .Soon after the intixxluctioii of the first- 

 s' 



