96 A PLANT-DISEASE SURVEY IN TEXAS. 



GROUND-CHERRY. 



Leaf -spot {Cercospora physaUcola Ell. and Barthol.).— This fimgus 

 on the ground-cherry {Phy sails sp.) produces circular brown spots 3 

 to 10 nini. in diameter, which show a marked concentric zonation. It 

 was found on only the lower leaves which were more or less shaded. 



Conidiophores amphigenous, few in each cluster, 130 to 150 by 5 ^, 

 several septate. Spores 60 to 130 ix or reaching 188 by 4 to 5 /*, five to 

 many septate, nearly hyaline. (PI. IV, fig. 5.) 



Our specimens differ from the type in having longer conidio- 

 phores, amphigenous instead of epiphyllous, septate instead of con- 

 tinuous, and larger, more numerously septate spores. 



Specimeu collected: New Braunfels, 1715. 



HORSE NETTLE. 



leaf-spot {Cercosipora atro-marginalis Atk.). — This disease appears 

 on the leaves of the horse nettle {Solanum carolinense L.) as circular 

 or somewhat angular dark-brown spots from 3 to 5 mm. in diameter. 

 These spots frequently a:re concentrically zonate, with a dark margin. 

 The conidiophores are densely fascicled and show as brown heaps 

 when aggregated. 



Specimen collected: Gonzales, 2667. 



HYDROCOTYLE. 



leaf -spot {Cercos'pora hydrocotyles Ell. and Ev.). — Very numerous 

 reddish-brown spots are produced on the leaves of hydrocotyle {Hy- 

 drocotyle spp.). They are circular or slightly angular, and 1 to 3 

 mm., mostly 2 mm., in diameter. The leaf tissue between the spots is 

 at first yellow, turning brown, with the fungous foci darker. The 

 conidia vary from 30 to 80 by 3 to 3.5 /x, exceeding the size given in 

 the original description (16), which measurement is 30 to 40 by 3 ii. 



Specimens collected: On H.umhcUata L.— Von Ormy,1117; San Antonio, 3165. 

 On H. vertmUata Nutt. — Georgetown, 2384. 



Rust {Puccinia hydrocotyles (Lk.) Cke.). — The rust appears on 

 the leaves of //. umbellata as minute circular brown pustules, often so 

 closely clustered as to give the leaves a brown color and cause their 

 death. 



Specimen collected : On H. umbellata L. — Von Ormy, 1117. 



INDIAN MALLOW. 



Rust {Puccinia heterospora B. and C). — This rust on the Indian 

 mallow {Ahutilon texense T. and G.) produces circular telia 0.5 to 3 



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