52 A PLANT-DISEASE SURVEY IX TEXAS. 



gray or dirty-yellow center, bearing a central cluster of black acervuli. 

 The acervuli are on both surfaces and few in each spot. The spores 

 are falcate, acute pointed, hyaline. 20 to '27 by 4: to 5 /*, and frequently 

 show one to three large granules. The conidiophores are short. 15 fi 

 long, and nonseptate. The seta? are pointed, with slightly bulbous 

 base. 1 to 2 septate, and reach 75 /x in length. (PL VI. fig. 15.) Our 

 specimens agree with C. Jineola Cda. in size of spores and seta? and 

 with C. andropogonis Zimm. 1 in symptomatology. 



One field was observed where the disease was sufficiently developed 

 to cause the death of the grass. 



Specimens collected: Round Rock. 2410 (type specimen). 2427; Falfurrias. 

 2441. 2727 ; Yoakum. 2753 : Floresville, 2S44 ; Austin. 3036. 



Rust (Puccima purpurea Cke.). — This rust occurs so abundantly 

 on the leaves that they are purple, the color being caused by the 

 closely clustered, elongated sari which rupture the epidermis on both 

 leaf surfaces. 



Specimen collected : Austin, 121. 



JUXGLE KICE. 



Gray-spot (Piricularia grisea (Cke.) Sacc). — Circular or oval yel- 

 lowish areas with purple margins appear on the blades of jungle rice 

 (EcMrmcMoa colona (L.) Link). These spots are from 1 to 5 mm. 

 in diameter and become grayish below. The intervening tissues are 

 killed and the leaf tips become dry. (See under " Crab-grass/*) 



Specimen collected : Uvalde. 1938. 



PAXicrvr. 



Black-blotch. (PhyUackora granrinis (P.) FckL). — The leaves of 



Panicum (Panicum spp.) become infested with black, shining, stro- 

 matic blotches. These are small, mostly less than 1 mm. in diameter. 

 and often confluent. The affected leaves become brown between these 

 spots. 



Specimens collected : Austin. S39 : Elgin. 1S95. 



Gray-^pot (Piricularia grisea (Cke.) Sacc). — Small elongated or 

 lenticular spots are formed. They are grayish brown with a brown 

 border, and are most abundant toward the tip of the leaf. Chlorosis 

 accompanies this spotting, and large parts of the leaves turn brown. 



Specimen collected : On Panicum texanum Buck. — Kennedy. 2S34. 



1 Dr. Zimmerman, to whom duplicates of our specimens were sent, reports that they are 

 identical with C. andropogonis Zimm. Edgerton. who is making a careful study of the 

 Colletotrichums. is of the opinion that C. lineola Cda.. C. andropogonis Zimm., C. cereaJe 

 Manns, and C. falcaium Went, may be identical. 

 226 



