72 A PLANT-DISEASE SURVEY IN TEXAS. 



under cultivation. This leaf disease causes a browning of the tips 

 of the lobes. The acervuli are sparsely present on the lower surface. 

 We were unable definitely to associate this fungus with any of the 

 ten species described as occurring on species of Acer. 

 Specimens collected: Victoria, 2520; Flatonia, 2716. 



MESQUITE. 



Anthracnose {Gloeosporium leguminuin (Cke.) Sacc). — The pods 

 of the mesquite {Prosopis glanclulosa Torr.) are quite generally 

 affected by a Gloeosporium, which produces irregular slightly sunken 

 areas on one side of the pods or completely encircling them. The 

 spots show numerous black acervuli, which are generally aggregated 

 and frequently confluent on a gray ground, and the whole area is 

 surrounded by a narrow zone of brown. Seriously affected pods fall 

 from the tree before they reach maturity. 



Specimens collected: Austin, 17; San Antonio, 1360; Beeville, 1796; Elgin, 

 1891; Uvalde, 1961; Hondo, 1996; Bastrop, 2046; Loclihart 2061; San Marcos, 

 2096; Cotulla, 2184; Luling. 2253; Seguin, 2314; Stockdale, 2609; Gonzales, 

 2662; Floresville, 2843. 



Blight. — The affected leaves in the early part of the growing season 

 show a pronounced yellow color on the upper surface, while large 

 numbers of minute yellowish heaps cover the under surface. The 

 affected leaves soon fall, and by midsummer they have entirely dis- 

 appeared. Thus far it has been impossible to associate the trouble 

 with any known organism. 



Specimens collected: San Marcos, 926; Austin, 1065. 



Galls. — The large limbs and smaller branches of the mesquite some- 

 times show abnormal enlargements which are frequently globular 

 or sometimes elongated and sometimes greatly exceed the diameter of 

 the branch on which they are produced. (PI. XV, figs. 2 and 3.) 

 Specimens have been obtained ranging from 1 to 8 or 10 inches in 

 diameter. The gall is produced by an abnormal growth of the wood, 

 and cross sections of galls always show small brown specks where the 

 wood cells are more or less disintegrated. These are distributed 

 throughout the entire woody region. 



These galls are not of insect origin, and cultural work attempted 

 has as yet failed to connect either bacteria or fungi with the disease, 

 although both have been obtained. 



Specimens collected : Austin, 1294 ; Llano, 1746 ; Beeville, 1858 ; Cotulla, 2218 ; 

 Runge, 2923. 



Mistletoe {Phoradendron favescens (Pursh.) Nutt.). — The Ameri- 

 can mistletoe is not uncommon on the mesquite. In some regions 



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