MYi.'UbO.MATIA oK T1IK ALDER, I i< 



101 



provisionally distinguished as Frankia alni (Wor. > on alder, and 

 Frankia Brunchorstii (Moll.) on .!//// />// <;L. 



HiltiU'i-, 1 after a series of experiments, stab-- that first-year 

 alders without tubercles do nut thrive in soil free from nitrogen, 

 nur do they take up nitrogen fVoni the atmosphere: when, 

 however, provided with root-tubercles they assimilate nitrogen. 

 The tubercles also functionate in \vater. and soil rich in nitrogen 

 has the affect of slightly increasing the assindlation of thai 

 element. Tlie tubercle-fungus is at first parasitic on the alder. 

 and is only of use to the plant after the tubercles have fully 

 developed. 



Mycodomatia of the Leguminosae. 



All Leguminosae urowinu in their native soils exhibit 

 so-called tubercles. These are accessory formations of 

 primary root-rind and are furnished with 

 vascular bundles connected with the root- 

 bundles ; they consist of a cortex of normal 

 cells surrounding an inner larp'-celled 

 parenchyma with turbid cell-contents con- 

 -i>tin^ of numbers of bacteria, (Hurt, //////* 

 ,;i,li, ,,!,!. I'.eyerink, or HI /://////// leguminos- 

 n i-ii in, Frank. )- 



I-'i-ank dcsciibcs minutely the formation 

 of these tubercles. 3 The short rod-shaped 

 micmbe forces its way into a root-bail- 

 or epidermal cell, multiplies there, and i- 

 cniiducted to the inner cortical cells by 



i 



pl.i-ma-thi'eads continuous through the 

 i-1-ll-walls. A rapid di\'isi<m of the inner 

 cortical cells is set up, till a tubercle is 

 formed, which may still further increase 

 by continued cell-division from a meridiem 

 at its apex. The bacteria multiply simul- 

 taneously, and are transferred into the 

 change come- over most of them 



the 



the 



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 phot) 



greal 



lliltn.-i, "Uebet -I. !! l-nl mi- .1. \\ in /c 



i' l.t iiri,i,,i,,,i'i. Vervuchs-stationen, IMI 



new cells \\here a 

 they eidar-e vci \ 



\ . . \lini^ 



- \Voroniii, M>' in. 'I' i'n, -ml. <l. , 



l.-h r>:ii,-lt ,/. I '.,.' nil;, 1 1. '-'71. 



Piternburg, 



