80 Bulletin 313 



CoNiOTHYRiuM coNCENTRicuM (Desm.) Sacc. — On the leaves of 

 Yucca and Agave, causing spots and dying of the tips. Spots cir- 

 cular or oval, or irregular, frequently confluent, yellowish, ashy, 

 surrounded by a broad, dark, regular to irregular border; pycnidia 

 concentrically depressed, dark, spores globose to ovoid, hyaline, be- 

 coming yellov^ish and finally fuliginous, 4-5 x 3-4 /x. 



448. Infected tip of Yucca leaf. 449. Spots on the leaf of Agava sp. 450. 

 Pycnidinm, 2/3. 451. Pycnidia with spore tendrils, 2/3. 452. Cross-section of 

 pycnidium from Yucca, 2/3. 453. Spores from Yucca, 1/12. 454. Spores 

 from Agava, 1/12. 



CoNiOTHYRiuM FUCKELii Sacc. (= LeptosphcFria coniothyriiim 

 (Fcl.) Sacc, page 48).^ — On raspberries and roses. Causes a blight- 

 ing and dying. The bark peels from the diseased part showing the 

 small black pycnidia. (Pycnidia will also form on cut surfaces of 

 canes in the moist chamber.) Pycnidia scattered, subcortical, 

 erumpent globose-depressed, 180-200 fi; conidia nimierous globose 

 or slightly elliptic, those on raspberry measuring 2.5-4.4 x 2-3 fi, 

 those on rose measuring 3-5 x 2-3.3 /t. 



455. Infected cane of rose. 456. Pycnidium from leaf with emerging 

 spores, 1/12. 457. Spores from same, 1/12. 458. Germinating spores, 1/12. 

 459. Pycnidium from leaf, 2/3. 460. Spores from same, 1/12. 461. Pycnidia 

 from cane, 2/3. 462. Cross-section of same, 2/3. 463. Same, 1/12. 464. 

 Hymenium from same, 1/12. 465. Spores from same, 1/12. 466. Germinating 

 spores, 1/12. 



CONIOTHYRIUM OLivACEUM Bon. grandiflorac Sacc. — On the 

 leaves of magnolia. Causes gray to brown circular or almost cir- 

 cular, sometimes irregular spots with definite margins, 1-5 mm. in 

 diameter. Pycnidia on the lower surface, globose, dark, about 

 100 fi in diameter; spores oblong or elliptical, olive-brown, 5-7 x 

 3-4 /t. 



467. Spores. 1/12. 



CONIOTHYRIUM PLATANi Sacc. — On the under surface of the 

 leaves of sycamore. Causes brown blotches visible on both sur- 

 faces. Pycnidia black, globose, erumpent. Spores very sm.all, 

 olivaceous to brown, unicellular, oval or nearly spherical, 3-3.5 x 

 2-3 /«.. 



468. Spores, 1/12. 



