HKMICKLLULOSES AND OTHKH CAUIIOHVUHATES. 39 



At tliiit timy nothing was known 1 . ;_'.inlin<r tlie prosonce of 

 cliitin in lunyi ; as, howi'Ver, tliis luttur siil).sttnf<' l»<'l»ii\ tvs like tlio 

 foinuT in presence of several of the colouring matteis employed 

 by Mancin, \Visski.i\(;ii (1.) thinks it not iiupiobal^le that the 

 two might he confountleil. 



From W'interstein's report thiit the fungoi<l cell niomhnine 

 preparations examined In' him ilitl not contain more than 3.9 

 per cent, of nitrogen, it nnist he conclmled that these mem- 

 branes were not exclusively composed of chitin, which contains 

 over 6 per cent, of that element, liut that con>ideriible (piantities 

 of other compounds, poorer in or altogether devoid of nitrogen, 

 were also pi-esent. 



At tiio jtresent time there is very little that is reliable known 

 with regar<l to the local distribution of the constituents com|K)s- 

 ing the cell membianes of fungi. Not that this deliciencv is 

 due to any l.ick of attempts tool>tain information on this point; 

 on the contrai-y, these date as far back as the efforts made by 

 W. FiKi.sTiNC! (I.) in 1S68. At a later period the matter was 

 energetically taken up by L. M.\N<:i.\ (11.), who repoited that, 

 in the Miirorintd examinetl by iiim, the inner layer of the .septii 

 and aerial hy[tha' consists of cellulose, whilst the outer layer is 

 compost'(lof pectin bodies. I'nfortunatfly the above-mentioned 

 obseivations of \\ i>S(lingh have seriously called in (piestion the 

 reliability of the microchemical reactions on which Mangin 

 based his assumptions. 



The reader will not expici to tind here any genenil lepoits 



on the thickness ot the cell membrane in fungi. Nevertheless, 



mention m.-iy be made, in this connection, of a fact determined 



by Fk. KscMKNH.vtiKN" (I.), namely, that the concentnition of the 



nutrient .S()lution luis a direct inlluence on the thickness of the 



cell membrane of the organism grt)wn therein. 



The cell membrane of fungi also often exhibits in a liigh 



. . . 



degree the capacity of swelling ; which, indeed, is fre4puMitlv an 



indispi-nsable faculty, especially in ajKO'cnii/ia and (/.<r». as being 



the oidy manner in which the endospores can be .set at liberty. 



It is, moieover, not infi-ecpiently found in the ca.se of vegetative 



cells, and will be dealt with in the paragniphs on the cell nu-m- 



brane of yea.st. Where mucination of this kind is encount4.>red 



one may r(>a.sonably a.ssume the pre.sence of pectin substances in 



the cell or menilirane. 



According to the concordant results obtained by A. lJriu;KK- 



STEIN (I.), M. NiGGL (I.), and C. C). Hauz (II.), lignitication of 



the nuMubraiie doe.s not seem to occur in Mucur miiccdo, Peiiicil- 



liutii i//(inrii)ii, Asj>er(;tllus ij/nurui^, and Sorrfiaromi/riii rrrtvisict, 



or, according to the ob.servations of the la.st-named worker, in 



j\Iucor nicfrirati^. Aspen/ill ii,t ro>ioi<li'us K^preii'/., Asp. ratKliiius 



Link., AsfK JJareso'iiii lioh., Cef>h(ilothe<'ium rosteufii, Tuhrr rifni- 



riuni, T. ifstivum, f'^'v''-'>p.'i jiur/nirea, and Torula. On the other 



