KHIZOI'E.I-'. 



75 



/^""^^^N 



which eUiselv lesomhle the liUizopeti- in iiiiiiiy other reHpeetu, 

 the Kponm^'iophuifs s|tiiii^' from pints of thi' luyceliuin that 

 are not iu any way sperially tli«tingiii>huhh' from tlie x-eht, 

 there is developed l)etween these two organs, in the Mortier- 

 fllu and Jtlii:.i>ji'',i, an inteiiiiediate or^'an which determines 

 the h)cation »jf the sporan^jiophore. 

 This is effected in the folhjwinjj 

 manner: a hypha, whicli, from its 

 peculiarities, is called a stolon, 

 be«;ins to project outwaid from the 

 mycelium ^(rtiwiii'r in and upon the 

 nutrient suh^tiatum. I)escriliin<r a 

 consideiiihle curve, this stolon endea- 

 vours t<) make its way to a sub- 

 stratum, which may either be a 

 distint portion of the nutrient 

 medium, or the walls of the vessel 

 in which the latter is contained. 

 The peculiar nutjitional movement 

 descrilied by the apex of the growinj; 

 stolon, was more closely examined 

 by J. WoliTMAXN (XIV.) in the csise 

 of Ji'/ii:.<>}'U,'< >iii/n'iHt/ij<. 0\i comiiif,' 

 into contact with the desired sub- 

 stratum, the st<)lon first endeavours 

 to attach itself thereto by puttinj; 

 forth a system of short hypha-, which 

 fit close a;,'ain.st the substratum, and 

 on account of theii- branched and 

 root-like form arc termed rhizoids. 

 In their entirety they const it uic ;iii 

 adhesive organ, called an appres- 

 sorinm, which is coj>iously su]>plied 

 by the stolon with nutrient materials 

 frtnii the distant mycelium, aiul in 

 tin-n puts forth stolons of the second 

 order. These now extend to farther 



distances and i>roduce aitpressoria of I'M-ha- (A), which h«vi. i.r.H-,f.icd 

 , , • , 1 • 1 r 1 '""" ""^ «toh>ii (»!>. Magn. loa 



the second order, wluih form the {,A/trr Bif/flJ.)^ 



starting point for stolons of the 



third or<ler, and »' on; and in this manner the vicitdty of the 

 nutrient substratum is overrun with a line network extending 

 over a considerable area. It is from this network, and not 

 from the mycelium itself, that the sporangiophores proceed, 

 springing from well-delined centres. Thus, in the case of the 

 genus I{/ii:(>/>ii,<, the sporangiophores take their rise exclu- 

 sively from the appres.soria, from each of which spring usually 

 three to five, more nirely tip to jvs many as ten. In the genus 



Mf 



■>•■., 



-■^nr 





fm. ii6.— Mortirrrlla lUxtathiskll 

 Bnfeld. 



The lower ciul i>i tlie »tM>ranf;io- 

 Iili^-rt' (f) is I'liVfloiHil tiy a |i|f\iii of 



