8 



The North American Cup-FuN(ii 



into the oogonium, after which the wall is rebuilt, cutting off 

 the oogonium once more as a single large cell. The male and 

 female nuclei now pair up within the oogonium and eventualh- 

 fuse, although again opinions differ as to whether they fuse in 

 the oogonium or merely pass in pairs through the ascogenous 

 h>phae, increasing by conjugate division, finally completing 

 their fusion in the ascus. The latter view seems to be the most 

 generally accepted one. 



The vegetative cells at the base of the archicarps and the 

 antheridia now put out a growth of sterile mycelium which 

 surrounds the ascogenous h>'phae, the two forming a compact 

 mass which constitutes the apothecium. 



Fig. 4. Sex organs of Ascobolus carbonari us. a, conidiophore with 



germinating conidium. b, antheridial conidiophore. c, coiled archicarp with 



trichogyne entwined about the antheridial conidium. d, ascogenous hx'phae 

 developing from enlarged cells of the archicarp. 



As shown by DeBary and other early workers the archicarp 

 in Ascobolus furfuraceus differs from that of Pyronema in that 

 it consists of a chain of cells of variable size, one of which near 

 the center functions as an oogonium and eventually produces 

 the ascogenous hyphae. 



While working as a student in The New York Botanical 

 Garden, B. O. Dodge, at the suggestion of the writer, took up 

 a study of the Ascobolaceae, which study has added much to 

 our knowledge of the morphology of this group of cup-fungi. 

 Perhaps the most interesting of his discoveries is the method of 

 reproduction of Ascobolus carbonarius which, unlike most of the 



