PEBISPORIAGE^ 



281 



Fig. 189.— The sexual process in Eryalphe Cichxyri- 

 acearum. «, threads of mycelium ; &, anthcridium; 

 c, carpogonium ; rf, young sporocarp ; e, older sporo- 

 carp. Highly magnified.— After CErated. 



carpogonium becomes divided in such a way that from one 

 portion of it an inner layer of cells is formed in contact with 

 the outer envelope described above. From the remaining 

 central part of the cai'pogonium one ascus (in SphcBrotJieca 

 and Podosphmra), and in the other genera two or more, are 

 developed. In each _e 



ascus from two to 

 eight ascospores arise 

 by internal cell-for- 

 mation (//, a, Fig. 

 188). The sporocarp 

 (technically called 

 the peritliecium) be- 

 comes dark and hard, 

 and from its outer 

 cells there grow out long filaments (technically known as 

 appendages), which are usually septate, and of a particular 

 shape in each genus ; thus in PodospJicera and Microsph(Bra 

 they are dichotomously branched ; in Pliyllactinia they are 

 straight and needle-shaped ; in Uncinula they are curved 

 regularly at their tips (Fig. 190), while in the other genera 

 they are tortuous, and simple or irregu- 

 larly branched. The perithecia remain 

 during the winter upon the fallen and 

 decaying leaves, and finally, by rupturing, 

 permit their asci, with their contained 

 ascospores, to escape. 



375. — There are usually present some 

 ^'S 19?.— Eipe sporo- other Organs, which bear small spore-like 



carp of Unomma adun- b ' ... 



ca; the appendages of bodics, but whosc function IS not certain 



the perithecinm are ' i . , 



■ " ■ known. These organs, which are 



ly 



curved in a circinate 



manner at their free ex- ^ . ,, , . . 



tremities.— After Cooke, known as pycnidia, are clavate, ovate, or 

 nearly spherical in shape ; the bodies they contain (the so- 

 called pycnidio-spores) in their cavities are usually oblong 

 or elliptical. 



376. — In the genus Eurotium (composed of saprophytes) 

 the conidia are produced in a slightly different way. The 

 mycelium, which is common on articles of food, as bread, 

 pastry, preserved fruit, etc., and on poorly dried specimens in 



