EXPLANATION OF PLATE /—(Continued). 

 Ehytisma line are PecK 



Page 100. 

 Fig. 24. A pine leaf bearing the Rhytisma along the midvein. 

 Fig. 25. An ascus containing spores x 400. 

 Fig. 20. Two spores, one involved in mucus, x 400. 



DiATRYPE {Diatrypella) betulina Peek. 



Page 101. 

 Fig. 27. A piece of a branch bearing the Diatrj^pe, the bark and two stromata 



having been removed from one end. 

 Fig. 28. A stroma magnified. 



Fig. 29. Vertical section of the same showing four included perithecia. 

 Fig. 30. An ascus magnified. 

 Fig. 31. Four spores more highly magnified. 



