390 



TEXT-BOOK OF FUNGI 

 Sphaeroideae 



All the species are individually very minute, but owing 

 to their gregarious habit often form conspicuous, broadly 

 extended patches. In Phyllosticta, a genus containing 

 between three and four hundred species for the most part 



FIG. 124. Entomosporium maculatum. i, quince 

 leaf showing blotches formed by the fungus ; 2, con- 

 idia with four slender appendages. Fig. i, nearly 

 nat. size ; fig. 2, mag. 



parasitic on living leaves, the perithecia are densely gre- 

 garious on bleached spots ; the perithecia are immersed in 

 the substance of the leaf and covered by the epidermis, 

 through which the ostiolum or mouth protrudes. The genus 

 Phoma, containing several hundred forms, is saprophytic 

 in habit, the minute, flask-shaped perithecia being usually 

 grouped in dense clusters, and forming, to the naked eye, 

 greyish or blackish stains on dead leaves, herbaceous stems, 



