-210 ASCOMYCETES. 



3. Brown, multiseptate conidia : 



(a) In brown, very large, smooth-coated pycnidia (Fig. 99, b). 



(b) In darker and smaller pycnidia with pointed aperture. 



4. Brown, bicellular conidia, in little dark pycnidia (Diplodia cytisi). 



B. PERITHECIA. 



">. Brown, multiseptate ascospores, in perithecia generally of dark colour, 

 and with depressed pore (Fig. 100). 



Cucurbitaria sorbi Karsten. This fungus appears to pro- 

 duce disease in a manner similar to C. lalmrni. It was described 

 by me in 1886 1 from specimens collected in the Bavarian 

 forest-land from young Pi/rus Aucuparia. They were easily 

 distinguished in August by their withered twigs, both bark and 

 wood being killed in tracts by the mycelium. In another 

 locality I found well-developed perithecia, also on P. Aucuparia. 



Cucurbitaria pityophila Fries, occurs on the living branches 

 of various conifers, e.g. Pinus Ccmbra. 



SPHAERELLOIDEAE. 



Stigmatea. 



The naked perithecia are superficially seated on the sub- 

 stratum. The ascospores, eight in each ascus, are clear and two- 

 celled. The species are parasites. 



Stigmatea robertiani Fr. (Britain and U.S. America). Occurs 

 on living leaves of Geranium Robcrtianum. 



St. ranunculi Fries. On living leaves of Rannnciilii* rcpcns 

 (Britain and U.S. America). 



St. mespili Sor. (U.S. America). This species appears in 

 spring as reddish-brown spots on the leaves of wild pear-trees. 

 At these places the epidermis becomes ruptured, and cushions 

 are formed from which brown conidia are given off from short 

 conidiophores. This stage was formerly known as .]/<>// ///Y/v 

 mespili. The conidia are at first obovoid, but later seem to 

 consist of four separate cells arranged in a cross, and each 

 furnished with a transparent bristle. Each conidium produces 

 a germ-tube which penetrates the epidermis, and in a month 



1 1 have since found from Saccardo that this fungus was described by Karsten 

 {.\fi/coL Fenn., it. "a,d.Ta,mosdejecioa Sorbi aticupariae in Fennia merid. et media"); 

 it was, however, unknown for Germany to that author. (Auth.) 



