ASCOMYCETES 195 



Sclerotinia Vaccinii (Wor.) Rehm. 1 This species occurs on 

 shoots, leaves, and berries of the cowberry, Vaccinium Vitis- 

 idcea. In this fungus the chains of conidia show characteristic 

 " disjunctors." The latter are fusiform cellulose structures sepa- 

 rating the spores, and apparently important in dissemination. 

 The conidial surface possesses an amygdaline aroma, by which 

 insects are supposedly attracted. The diseased berries are yell<5w- 

 brown when ripe. From sclerotia in mummied fruits which have 

 lain on the ground over winter the apothecia are developed. The 

 mature ascospores measure 14-17 X 7-9 p. 



Sclerotinia Aucupariae Ledw. 2 has been found in Finland and 

 in Germany on the leaves and fruit of Pints Aucuparia. 



Sclerotinia baccarum Schroet. 3 is the cause of the sclerotial 

 disease of the bilberry, Vaccinium Myrtillus. In this species the 

 apothecia are relatively large and stout, measuring 5-10 mm. in 

 diameter, with stalks often 5 cm. in length. The spores are 

 18-20 x 9/4. 



Sclerotinia megalospora Wor., 3 on the berries and leaves of the 

 crowberry, Empetrum nigrum, has large, more nearly spherical 

 conidia than those above described, and the ascospores, invested 

 with a distinct gelatinous envelope, measure 20-25 x 14-16/4. 



Sclerotinia Oxycocci Wor. 3 produces the sclerotial disease of the 

 cranberry, Vaccinium Oxycoccus. This species is morphologically 

 and physiologically interesting on account of the difference in 

 size of the spores, four being large and capable of germination, 

 while the other four are considered to be ill developed and in- 

 capable of germination. This suggests an interesting differentia- 

 tion of the nuclei. Even the larger spores are relatively small for 

 this group, measuring 12-14 X 6-7/4. 



Sclerotinia heteroica Wor. & Nawasch. 4 According to Woronin 

 this species produces upon Vaccinium uliginosum a conidial stage, 

 which conidia are able successfully to infest the ovaries of Ledum 

 palustre, but no conidia are produced on Ledum. On the latter 

 host, however, the sclerotial stage is developed. This fungus 



1 Woronin. Ueber die Sclerotienkrankheiten d. Vaccinieen-Beeren, /. c. 



2 Woronin. Ber. d. deut. hot. Ges. 9 : 102-103. 



3 Woronin. Ueber die Sclerotienkrankheiten d. Vaccinieen-Beeren, /. c, 

 *Nawaschin. Ber. d. deut. bot. Ges. 12 : 117-119. 



