116 THE PHYCOMYCETES 



PiNCKARD, J. A., Ruth McLean, F. R. Darkis, P. i\I. Gross, and F. A. 

 Wolf, "Toxicity of paradichlorobenzene in relation to control of to- 

 bacco downy mildew," Phytopathology, 50:485-495, 1940. 



Wager, H., "On the fertilization of Peronospora parasitica,'^ Ami. Botany, 

 i^; 263-279, 1900. 



Weston, W. H., "Nocturnal production of conidia by Sclerospora graiJii- 

 nicola;' J. Agr. Research, 21:111-1%^, 1924. 



Weston, W. H., and G. F. Weber, "Downy mildew {Sclerospora gramini- 

 cola) on everglade millet in Florida," /. Agr. Research, 55:935-963, 1928. 



Wilson, G. W., "Studies in North American Peronosporales. II, Phytoph- 

 thoreae and Rhvsotheceae," Bull. Torrey Botan. Club, 34: 387-416, 1907. 

 VI. "Notes on miscellaneous species," My col., 6: 192-210, 1914. 



Wolf, F. A., L. F. Dixon, Ruth AIcLean, and F. R. Darkis, "Downy mil- 

 dew of tobacco," Phytopathology, 24: 337-363, 1934. 



Wolf, F. A., Ruth A. McLean, J. A. Pinckard, F. R. Darkis, and P. M. 

 Gross, "Volatile fungicides, benzol, and related compounds, and the 

 principles involved in their use," Phytopathology, 50:213-227, 1940. 



iMUCORALES 



The Mucorales, commonly called "black molds," comprise 

 about 30 genera and 450 species. They are mostly saprophytic on 

 plant or animal tissues. Although a few species are pathogenic, 

 others are of considerable importance in the decay of fruits and 

 vegetables, and several are utilized in industrial processes. Absidia 

 corymbifera is associated with human bronchomycosis, A. cor- 

 nealis with lesions of the cornea, and Aiortierella niveo-velutina 

 with inflamed, intensely prurient, papular skin lesions; Rhizopiis 

 nigricajis produces a destructive decay of sweet potatoes that 

 have not been properly cured before being placed in storage. 

 These mentioned species and a number of other Mucorales are 

 pathogenic to laboratory animals. Choanephora ciiciirbharinn 

 is widely parasitic on squash flowers and fruits and also on cow- 

 pea. Rhizopiis oryzae and Ahicor javaniciis saccharify starch and 

 can be used in alcoholic fermentation. Several species of Rhizo- 

 pus are employed in lactic fermentation. Aiortierella bainieri, 

 Fiptocephalis freseniana, Dlspira cormita, and Farasitella (Aliicor) 

 simplex are parasitic on other Mucorales. Their parasitism is 

 generally regarded as restricted to other Mucorales, but Dobbs 

 (1942) reported that a species of Fiptocephalis, near P. tieg- 

 hemiana, is parasitic on Fenicilliinn notatiim, P. roqiieforti, P. 

 glabrum, P. pfefferiamim, and Aspergillus mger, as well as Ahicor 

 miicedo and Al. hiemalis. Species of Pilobolus are coprophilous. 



