86 



Forest Club Annual 



densely gregarious. The appendages number from 5-22, with tips 

 4-5 times dichotomously divided. Branches of the first and 

 second order are very short, all of the segments deeply divided, 

 ultimate branches forming a narrow fork, tips not recurved. Asci 

 4-10. On : Sambucus canadcnsis. 



Microsphaera diffusa C. & P. 



The persistent mycelium covers both sides of the leaves in 

 this species, in thin effused areas. The perithecia are scattered 

 or gregarious. The appendages are A 30, branching of the tips 

 diffuse and irregular, tips of the ultimate branches not recurved. 

 On : Symphoricarpos occidentalis, and 5\ symphoricarpos. 



Phyllactinia 



The perithecia are very large in this genus, and are flattened 

 or lenticular. The appendages are few, equatorially placed, rigid, 

 needle-like with a 

 large bulbous infla- 

 tion at the base. See 

 fig. 14. 



Phyllactinia corylca 

 (Pers.) Karst. 



In this species 

 the perithecia are 

 large, flattene '^-len- 

 ticular, and the ap- 

 pendages are few. 

 The appendages are 

 equatorially placed, 

 rigid, acicular, with a 

 large bulbous infla- 

 tion at the base. See 

 fig. 14. In this, the 

 only species, the my- 

 celium is usually con- 

 fined to the lower 

 surface of the leaf. 



The .peritbecia are widely scattered over the scanty mycelium. 

 The conspicuous needle-like appendages form a ring about the 

 large perithecitim, but they are easily broken off. The asci num- 

 ber 4-8, with usually two large well developed spores per ascus. 

 On: Cclastrus scandens, Cornus stolonifcra, Fraxinus lanceolata, 

 Ostrya 7'irginiana- and Xanthoxylum amcricanum. The large 

 black perithecia and the fringe of odd appendages that may be 

 seen with a hand lens are sufficient to distinguish this species. 



Fig. 14. Phyllactinia. a. Perithecium 

 with appendages, b. Ascus with spores. 

 Highly magnified. 



