238 BOTANICAL GAZETTE [October 



pycnidia in various stages of development (figs. 28-33). The 

 simple meristogenous development of the primordium is similar 

 to that described for Phoma herbarum West (figs. 1-5). 



Phoma cichorii Passr.; isolated from Phlox divaricata L. by 

 Mrs. Esther Young True, at Urbana, IlHnois, November 191 7. 



A few adjacent cells of a single hypha or of a number of con- 

 tiguous hyphal strands divide into short cells (figs. 34, 35). By 

 budding and swelling, short hyphal branches arise, the cells of 

 which swell and divide (fig. 36). The cells of the mother strand 

 or strands also enlarge and divide. The component hyphae 

 anastomose, forming a pseudoparenchymatous, irregularly rounded 

 mass. This mass develops into the pycnidium. The develop- 

 ment of this fungus differs from that described for the other species 

 in that, where only a single strand is involved, the mode is simple 

 meristogenous with the original cells and their budding branches 

 anastomosing to form the mass (fig. 36). In instances where 2 or 

 more strands are involved (fig. 37), there has been a similar division, 

 swelling, and branching in each strand, but the whole has been 

 united into a single primordium as described for Phoma destructiva 

 (fig. 22). This mode is compound meristogenous. 



Macrophoma (Sacc.) Berl. and Vogl. 



Macrophoma citruUi (B. and C.) Berl. and Vogl.; isolated by 

 Dr. J. A. Elliott from a cantaloupe {Cucumis melo L.) leaf pro- 

 cured from Alabama in the autumn of 191 5. 



Young pycnidia and small sclerotia form in abundance, soon 

 rendering the culture dark brown or black. Usually a single cell 

 in a hypha becomes slightly swollen. It then divides into 2 short 

 cells (fig. 38). These cells in turn divide by cross, longitudinal, and 

 diagonal walls (figs. 39, 40). The swelling continues until the body 

 becomes a rounded or oblong mass much darker than the light 

 brown mycelium (figs. 46, 47). The cells immediately adjacent 

 to the dividing mass may divide into short cells and send out hyphal 

 branches (figs. 42-44). The outer cells of the mass may also send 

 out branching hyphae. The hyphae from all these sources form 

 a network about the enlarging mass. Sometimes the hyphal 

 branches fuse with the mass, and in other cases they appear to 



