-7- 



working with were really the imperfect stages of a Sclerotinia that 

 he called the two forms Sclerotinia fructigena and Sclerotinia cinerea 

 instead of Monilia fructigena and Monilia c in area. 



He gives for the average site of the conidia of Sclerotinia 

 f ructigena taken from tha surface of naturally infected pears and apples, 

 which have fallen to ihe ground, as 20.9 x 12.1 microns. Tha maximum 

 measurements for conidia produced in the open he gives as 24.5 x 13.2 

 microns. In cultures on different favorable media the site of the conidia 

 increases still more, reaching 20.7 - 30.8 x 14.9 16.5 microns. 



Spores of Sclerotinia cinerea taken from leafy shoots of cherry 

 and peduncles of cherry blossoms and from the surfaces of different 

 stone fruits average 12.1 x 8.8 microns.* Ha says however, that tha 

 ete is not constant. The largest spores of Sclerotinia cinerea col- 

 lected by him in the open raeaeura 13.2 x 9.9 microns. Spores in 

 cultures on different favorable madia are larger, and measure usually 

 17,5 x 11.2 microns. Single spores he adds in the favorable culture 

 media msy reach even 24*2 x 13.2 microns. 



Woronin found the most striking difference between thase two 

 forms to lie in the general form and color of the conidial pustules. 

 Sclerotinia f ructigena produced the compact knob-like yellondsh pustules, 

 w kil Sclerotinia cinerea produced the grayish more powdery pustules. 

 See Plate 28 for copies of the color blocks appearing with Woronin* s work. 



Aderhold and Huhland (3) in 1905 claim the distinction of 

 rediscovering the species laxa. In their work they compare the 

 apothecial stage of the species they call lexa with the apothecial stags 



