< i < i I;I;ITAI;IA. 



L'n 7 



an acute beaked pore. Where the bark has been l.-t, a 

 good lens may distinguish th> j spherical or nv<id dark-coloured 

 perithecia. On the tiner twins the whole 

 bark is often perforated by numerous, tiny 

 pycnidia, hardly distinguishable with the 

 naked eye. 



If these various forms of fructification be 

 -ubinitted to microscopic examination, sections 

 through the yellow pu-tule.x will show them 

 to have that colour, because the transparent 

 periderm has liecorne loosened from the real 

 of the bark; underneath the corky la\ >i- 

 will lie found a red stroma of pseudo- 

 parenchymatous hyphal tissue. This stroma 

 by its growth causes a gradual rupture and 

 loosening of the corky and other layers of the 

 periderm: wherever this takes place, conidio- 

 phores are developed, and ^ive off numbers of 

 tiny, hyaline, ovoid or cylindrical conidia. 

 The stroma it. -elf is somewhat spongy, and 

 encloses numerous cavities which also become 

 lined with conidiophores. At a later period 

 the tissue enclosing these cavities may become 

 dark coloured, so that structures similar to 

 pycnidia are formed. In such cavities the 

 red colour disappear-, and the hyphae, c<>ni- 

 diophores. and conidia appear transparent. 

 The ival pycnidia appear later, and COHSlSl >!' 



a jieridium of coarse pseudoparenchyma con- 



taining conidia similar to those just described 

 < Fiv. '.''.', A). From the 

 iii tlie conidia 



s 



rising 



aa much as one 

 pop-. Adjoining the-r 



jii-t de-cribed \\ ill be 

 veloped perithecja with 



pycnidia 



Jeptate eom|ioiin 

 \\itb unicellular 



Wlh'le the di 



these 



-e as red tendrils. 

 cent iniet iv above the 

 Idi-ms of sporophure 



found othere : unde- 



\ min- asci ; dark- 

 nmlti- 



with brownish-'ji<-\ 



ci.nidia 

 ,-plierical 



a- 



or .-i mi far p\ cn 

 bin\\ni li -ie\ 

 made tllllliel' 



i 



i 'i mi Hi i 



burn urn (diagramtD 



.-till Inn 

 full i. 



iin^ -nun 



| 

 I'iml i- <\>-.\<\ :in>l tin- 



;in ' 



. 



.ui'l ' 



pl'i 1 1 he pll-tl 



