252 BOTANICAL GAZETTE [October 



Variations of these 3 modes of development are found. No 2 

 species give exactly the same development. In symphogenous 

 development a few branches from nearly hyphal strands may inter- 

 weave near their ends, or intermingling hyphae may loop back, 

 branch, and interweave or snarl into a knotlike mass. In the 

 simple meristogenous mode the origin may be a single cell which 

 swells and divides, or a number of cells that swell and divide 

 simultaneously. In some cases branches arising from the dividing 

 cells anastomose with the enlarging mass. In other cases branches 

 arise from more distant cells of the same strand and take part in 

 the development. In a few instances short budlike branches 

 arise from a few cells of a hyphal strand, enlarge, divide into short 

 cells, intertwine, and anastomose to form a pycnidium. 



Neither have the acervuli-forming fungi in the Melanconiales 

 been studied as to the early development of their sporing bodies, 

 nor has the origin of the sporodochium been given special attention. 

 Sherbakoff (37), in studies of Fusarimn, describes a simple type 

 of sporodochium found in cultures. Tulasne (43) , Stoneman (42) , 

 SouTHWORTH (38, 39), WoLF (50, 51), and others figure and describe 

 later stages of the development of acervuli, and the later develop- 

 ment of sporodochia are referred to in the literature, but the subject 

 is considered merely incidentally. 



The fungi that form acervuli and sporodochia may be classed 

 according to the manner of origin and development of the primordia 

 on the same basis as the pycnidia-forming species. 



In table II fungi of the Melanconiales and Tuberculariaceae 

 that were studied are listed, indicating the method or methods 

 of development of the primordia. In Gloeosporium rufomaculans , 

 Gloeosporium musarum, and Pestalozzia guepini the primordia 

 originate by the symphogenous method. In Colletotrichum lage- 

 narium and Vphitella circinans the symphogenous method prevails, 

 although the simple meristogenous mode occurs occasionally. The 

 compound meristogenous mode is well exemplified by Pestalozzia 

 palmarum, Pestalozzia from peony and from maple. Epicoccum 

 and Pestalozzia from maple have only the compound meristogenous 

 mode. The simple meristogenous method of development appears 

 in Colletotrichum lagenarium, Pestalozzia palmarum, Pestalozzia 



