I>AM -. ^ 1'IIA. 1'71 



Dasyscypha (Peziza) Willkommii. Hai-ti-. 1 The I.aich ('ankei 

 (I'.iitain and I'.S. America i. Fvcrywhere in the mountains, tin- 

 home of the larch, one finds, on youn- l>ranelte- and old -tem-. 

 depressed canker-spots, on which the sporocarps of A/.s//.^//^/^ 

 //'////, '-,//,////' are de\-clo]ied. Young twigs, when attacked, are 

 already conspicuous in .July and August by their pale and 

 withered needles, and on them small 

 canker-spots will lie found; these rapidly 

 enlarge so that on older stem- they may 

 reach very great dimensions. Hartig ea-ilv 

 succeeded in producing canker-spots on 

 healthy tree- by artificial infection. 



If canker-spots are examined soon after 

 the death of the bark, the stromata will 

 be found as yellowish - white pustules. 

 Conidia are produced either on the free 

 surface or in the internal cavities of a 

 stroma : they are tiny unicellular hyaline 

 bodies, produced from little conidiophores. 

 Hartig never succeeded in getting these 

 spores to germinate. If the atmospheie 

 be moist enough the apothecia make their 

 appearance later on the same places; they 

 are externally yellow, and internally orange- 



. . ,.',. * i'ii- i lf'illl:iniiiii. Three :i-ci aii'i 



coloured. Ine apotneciaJ disc carries Long two paraph] 



. ii-i i i* i i from an apotheclum. i 



thread-like paraphy.-es and cylindrical asci it. ii:,i;i-.) 



with rounded apices ( Fig. 14.'!). The asco- 



spores are oval, unicellular, and hyaline. They -crminale and 

 give off one or two geriu-tiibo which are unable to penetrate 

 tin- pcrideriu of a host-plant, and only find entrance through 

 wounded place-. Wound- are very common on larch as the 

 re.-ult of hail, or injury t tuins by snow or ice, or destruction of 

 needles by insects. For example, the 1. arch-moth ( f' ( //,, </</' 

 Iti nrillii) is well known to cause less damage on the niounlain- 

 than iii the lo\\cr regions, and in the same de-r.-c /)>i-<i/vi/j>/t<f i- 



i injiiiiou- to mountain forests. 



The mycelium i- septate and much branched: it spread- 

 chiefly through the -oft l,a-t. e-peciall\ ill the -i. \ . I ii 1 M-- and 



Fi... 



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K. 



ij, Unternuch. n /,/</;/. / 



.I///./ / ; det II ' " -. it.. I -'- 



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