70 A PLANT-DISEASE SUEVEY IN TEXAS. 



pycnidium contains brown spores, 15 by 6 ju, and three septate. It is 

 probably merely associated with a physiological languor, coming in 

 as a saprophyte. 



Specimen collected: Gonzales, 2698. 



Leaf -spot {Oercospora crataegi Heald and Wolf, 32). — This fungus 

 causes the formation of large, dark-brown, irregular areas from 5 to 

 10 mm. or more in diameter. The spots are darker above than be- 

 low, and when as many as 20 to 25 in number are confluent, involv- 

 ing large areas, with chlorotic tissue surrounding them. The upper 

 surface is broken by the numerous brown tufts of conidiophores and 

 conidia. The conidiophores are closely aggregated, 24 to 30 by 5 to 

 6 [M, brown and nonseptate. The conidia are clavate, straight or 

 curved, 120 to 180 by 5 to 7 /*, many septate with prominent guttulae. 

 (PI. IV, fig. 2.) 



Specimen collected: Gonzales, 2697 (type specimen). 



Rust {Gymnosporangium globosum Farl.). — The cluster cups of 

 this rust were found abundantly present on the leaves and twigs of 

 Crataegus crus-galli L. (See under " Cedar.") 



Specimens collected: Austin, 1312, 1444 (cluster cups). 



Rust {Gymnosporangium sp.). — Several species of Crataegus have 

 been found whose leaves are covered by reddish-yellow areas, with a 

 group of black spermagonia at the center. 



Specimens collected : Elgin. 2009 ; Lockhart. 2069. 



HEMP THEE. 



Leaf-spot {Oercospora viticis Ell. and Ev.). — Irregular, suborbicu- 

 lar, rusty spots, 2 to 4 mm. in diameter are formed on the hemp tree 

 (Vitex agnus-castus L.). The margin of the area is elevated and 

 darker, with a paler center as the spots become old. 



Specimen collected: Nursery, 2569. 



JAPANESE IVY. 



Leaf -spot (Phyllosticta labruscae Thm.). — The spots produced on 

 the Japanese ivy {Psedera tricuspidata (Sieb. and Zucc.) Render) 

 by this fungus are subcircular, 5 to 8 mm. in diameter, reddish brown, 

 with a narrow dark border. The black pycnidia open to the upper 

 surface. 



Specimen collected: Austin, 3103. 



LILAC. 



Leaf -blight {Oercospora macromacidans Heald and Wolf, 32). — 

 This blight on the lilac {Syringa sp.) is characterized by the pres- 



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