12 



Mycologia 



The common hackberry of this region, Celtis mississippiensis, 

 is quite generally affected with a serious leaf blight which first 

 produces irregular gray blotches 1-2 cm. in diameter. These 

 blotches sometimes coalesce and involve a large part of the leaf. 

 In early stages of the disease the adjacent tissue may remain 

 green, but later a considerable amount of yellowing is produced 

 and the affected leaves fall from the tree. The acervuli are 

 amphigenous, but more abundant upon the upper surface. The 

 spores are extruded in masses and accumulate on the surface of 

 the leaf where they are visible as minute white tufts. This 

 species is clearly distinct from Cylindrosporium Ceitidis Earle, 

 which has been described as forming small spots on Celtis 

 mississippiensis in Alabama. 



Cylindrosporium griseum 



Maculis variis, numerosis, orbicularibus vel leniter angulatis, 

 1-5 mm. latis plerumque 1-2 mm., saepe confluentibus ; acervulis 

 amphigenis, in venis, orbicularibus vel elongatis, maturitate atris ; 

 conidiis cylindraceis, leniter curvulis, hyalinis, 7-9-septatis, 

 90-135 X 3-4-5 /*. 



On leaves of Sapindus marginatus Willd. Kerrville, 1588; 

 Llano, 1757 (type) ; Bastrop, 2026; San Marcos, 2098. 



Very numerous grayish or whitish, circular or slightly angular 

 spots are produced on both surfaces of the leaflets and the rachis ; 

 and show more prominent veins owing to the shrinking of the 

 tissue. These spots may become confluent and cause extended 

 dead areas. The acervuli are amphigenous, more abundant on 

 the upper surface, and are located immediately over the promi- 

 nent veins. They may be nearly circular in outline or much 

 elongated along the veins, pale when young and becoming darker 

 with age. 



Cylindrosporium Lippiae 



Maculis 2-3 mm. diam., centro griseolis, margine angusto 

 brunneo cinctis ; acervulis amphigenis, plerumque epiphyllis, 30- 

 100 /x diam.; conidiis subcylindraceis, hyalinis, continuis vel 1-3- 

 septatis, 24-54 X 3 



On leaves of Lippia ligustrina Britton. Llano, 1756 {type). 



This fungus produces three or four circular spots on each leaf. 



