THE FUNGI WHICH CAUSE PLANT DISEASE 163 



Hysteriaceae (p. 160) 



Ascocarps free, seated upon the substratum, 

 elongate or linear, straight, curved or even 

 branched, disk-form, boat-shaped or band-like, 

 black; asci usually 8-spored; paraphyses fila- 

 mentous, often forming an epithecium. 



About fourteen genera and some two 

 hundred fifty species, many but poorly 

 known. Several genera contain plant patho- ^^°: 116.--D. quer- 



. . cma. Ascus and 



gens, but they are not often of economic im- paraphyses. After 



Rehm. 



portance. 



Key to Genera or Hysteriacese 



Ascoma linear, flattened, broadly sessile 

 Spores ellipsoid or spindle-shaped, many- 

 celled 



Spores 1-celled, 16 in each ascus 1. Cyclostomella. 



Spores 2-celled, sometimes 4-celled, 

 ellipsoid or elongate 

 Spores hyaline 

 Asci 8-spored, spores 2 to 4-ceUed 

 Paraphyses scarcely branched. 2. Aulographum. 

 Paraphyses forming an epithe- 

 cium 3. Glonimn. 



Asci many-spored, spores 2-celled . 4. Hariotia. 

 Spores colored, 2-celled; leaf infect- 

 ing fungi 

 Paraphyses present 

 Ascoma seated on a cottony 



stroma 5. Lembosia. 



Ascoma radial, on a circular 

 stroma 

 Spores 2-celled, 8 in each 



ascus 6. Parmularia. 



Paraphyses absent, stroma irreg- 

 ularly circular 7. Hysterostomella, 



Spores 4 to 8-celled, elongate or spmdle- 

 form 

 Spores hyaline, spindle-form, 4- 



celled 8. Hysteroglonium. 



