26o BOTANICAL GAZETTE [ocxober 



Fig. 87. — Side view of an acervulus formed by symphogenous method: 

 compressed so that cushion-hke bed of conidiophores is pulled away from basal 

 hypha. 



Fig. 88. — G. musarum C. and M.: top view of partially developed acer- 

 vulus; development symphogenous. 



Colletotrichum 



Fig. 89. — C. lagenarium (Pers.) E. and'H.: very early stage in which 

 acervulus originates in a few short branches from a single hypha. 



Fig. 90. — Numerous budding branches from a few cells of one hypha 

 forming beginning of an acervulus; simple meristogenous. 



Fig. 91. — Early stage in development of acervulus. 



Fig. 92. — Primordium in which a few branches are involved. 



Fig. 93. — Early stage in symphogenous development: hyphal branches 

 loop and interweave in this mode. 



Fig. 94. — Same as fig. 93, 24 hours later. 



Fig. 95. — Beginning stage of symphogenous development. 



Fig. 96. — Later stage. 



PLATE XXI 



Pestalozzia 



Fig. 97. — P. palmarum Cke. : a, very early stage in meristogenous develop- 

 ment, a few cells divided and swelling; h, later stage. 



Figs. 98, 99. — Pycnidia with young spores developed within. 



Fig. 100. — Primordium of compound meristogenous origin. 



Fig. ioi. — Young pycnidium at stage just before opening. 



Fig. 102. — Pycnidium opening and extruding spores: following this stage 

 cuplike interior formed, longer conidiophores develop, and body becomes a 

 pseudo-acervulus . 



Figs. 103, 104. — P. guepiniDesm.: early stages in symphogenous develop- 

 ment. 



Fig. 105. — Later stage; pycnidia of this species form spores within and 

 later break open as pseudo-acervuli. 



Fig. 106. — Pestalozzia from peony: meristogenously developed pycnidial 

 mass. 



Fig. 107. — Early stage in symphogenous development. 



Fig. 108. — Later stage. 



Fig. 109. — Pycnidium which has opened, surface view. 



Fig. no. — Pestalozzia from maple: compound meristogenous develop- 

 ment from a number of parallel hyphae. 



Fig. III. — Later stage. 



Fig. 112. — Young pycnidium breaking open on one side: spores show 

 within. 



