DISEASES OF TRUCK CROPS. 39 



spores (10). Present only on languid leaves and not sufficiently 

 abundant to cause any material injury. 

 Specimen collected: Georgetown, 2367. 



CARROT. 



Rhizoctonia root-rot {Corticiimi vagum B. and C. var. solani 

 Burt.). — The roots of the carrot {Daucus carota L.) become covered 

 by white, ropy strands of the fungus. No serious rotting was ob- 

 served to result. 



Specimen collected: San Antonio. 



CASABA. 



Sooty mold {Fumago vagans (?) P.). — The mycelium on casaba 

 ( CuGUTnis melo L. ) forms a black or brown sooty crust on the leaves, 

 most abundant on the upper surface. Plant lice were abundant on 

 the foliage. 



Specimen collected : New Braunfels, 1725. 



CUCUMBER. 



Root-knot {Heterodera radicicola (Greef) Mill.). — Vines of the 

 cucumber (Cucumis sativus L.) which were affected remained stunted 

 and later were killed. In one field about one-third of the plants were 

 dead by the time they should have been bearing. 



Specimens collected : Austin, 3138 ; San Antonio, 3146. 



EGGPLANT. 



Fruit-rot {Gloeosporium melongenae Ell. and Hals.). — The fruits 

 of the eggplant {Solanum melongena L.) affected with fruit-rot show 

 brown, sunken areas over which are scattered the black acervuli. 

 With the progress of the disease the fruits are completely rotted. 



Specimens collected : Austin,. 1906 ; Uvalde, 1943. 



Fruit-rot {Collet otrichum sp.). — On the diseased areas are very 

 dense aggregates of black acervuli, varying in diameter from 100 to 

 250 n- Brown, taper-pointed, septate setae, 100 to 150 by 5 /x project 

 profusel}^ from all parts of the acervrdus. The conidiophores are 

 slightly club shaped, 12 to 15 by 3 to 4 /n, and the spores are 30 to 36 

 by 3 to 4 ju, clear, guttulate, falcate, frequently blunt on one end. 

 This has not been definitely associated Avith any described species and 

 may represent a new species. Gloeosporiiim melongenae was also 

 present on the same fruits, which were completely destroyed by the 

 combined action of the two fungi. 



Specimens collected: Austin, 1915, 2430. 



226 



