216 THE FUNGI WHICH CAUSE PLANT DISEASE 



Key to Gknera of Dothidiaces 



Stronmta at first sunken later more or less 

 free 

 Perithecia standing free on the stroma; 



spores at maturity, 4-celled, dark I. Montagnella. 

 Perithecia ahuost completely embedded 

 in the stroma 

 Stromata variable, more or less irreg- 

 ular in outline but never elongate 

 Spores I-celled 

 Spores hyaline 

 Asci typically borne at the 

 base of the perithecium 

 Asci 8-spored 

 Spores ellipsoid 



Perithecia few 2. Mazzantia. 



Perithecia numerous. . 3. Bagnisiella. 



Spores filiform 4. Ophiodothis. 



Asci many-spored 5. Myriogenospora. 



Asci borne laterally at the 

 equator of the perithe- 

 cium, spores ellipsoid ... 6. Diachora, p. 217. 



Spores brown 7. Auerswaldia. 



Spores 2-celled 

 Spores hyaline 



Spores ovate 8. Plowrightia, p. 217. 



Spores needle-like 9. Rosenscheldia. 



Spores colored 

 Cells of the spore similar. ... 10. Roussoella. 

 Cells of the spore dissimilar. . 11. Dothidea, p. 220. 

 Spores several-celled 

 Spores with cross walls only 



Spores hyaline, 4-celled 12. Darwiniella. 



Spores colored, multicellular 13. Homostegia. 

 Spores muriform 



Spores hyaline 14. Curreyella. 



Spores colored 15. Curreya. 



Stromata elongate, linear or lanceo- 

 late 



