

2go BOTANICAL GAZETTE [april 



in fig. 5 is shown much enlarged. It will be noticed here that the 

 tips of the hyphae at the periphery stain very deeply. This is 

 probably due to the fact that, since growth is taking place much 



more 



much 



ns as the result of metabolism more deeply staining contents, 

 certain young fruit bodies (fig. 4) the setae are developed 

 earlier than in others. The reason for this is not known. 

 They are prominent organs, originate from the deeper lying tissue 

 of the fruit body, and protrude beyond the palisade layer as deep- 

 staining spines. These are shown much enlarged in fig. 14. It 

 will be noted that they are of much greater diameter than the 

 other hyphae of the ascocarp. They arise as differentiations of 

 ordinary vegetative hyphae. 



Sexuality. — Near the center of the sections shown in figs. ' 



and 5 are to be seen deep-staining elements. These bodies con- 

 stitute the sexual apparatus of the fungus, and at a somewhat 

 later stage (fig. 9) give rise to the ascogenous hyphae. Since the 

 writer is engaged in the preparation of another paper dealing with 

 the details of the sexual process in Rhizina undulata, he will refrain 

 from further comment on these structures at this point. 



Paraphyses. — The layer of paraphyses is developed compara- 

 tively early in the history of the fruit body and constitutes a well 



m • 



defined zone long before the asci are produced. Fig. 7 shows a 

 median longitudinal section through a young apothecium on the 

 upper surface of which the layer of paraphyses is being differ- 

 entiated. In fig. 8 this same layer is shown more highly magnified. 

 The paraphyses arise from the ordinary hyphae in the interior of 

 the fruit body, and are in reality a specialized portion of the palisade 

 layer. As the fruit body enlarges by the elongation and branching 

 of the hyphae at the periphery, those palisade hyphae which lie on 

 the upper surface increase in number, run more nearly parallel, 

 and come to stand very close together. They soon constitute a 

 well defined zone, the individual units of which appear straighter, 

 slightly narrower, and many times more abundantly septate than 

 the palisade hyphae covering the remainder of the fruit body. 

 This layer of paraphyses continues to develop at the margin as the 

 fruit body increases in diameter, the line of demarcation between 



