ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 495 



Soil Fungi.* — F. C. AVerkentliiii gives an historical account of the 

 study of soil fungi, aud gives a resume of the results obtained by 

 different workers. His own investigations comprised the examination of 

 three different kinds of soil taken at various seasons from (1) a cotton- 

 field ; (2) from flower beds of the Univerrsity greenhouse ; and (3) from 

 the University campus which had lain undisturbed for twenty years. 



In his summary of results he states tliat : — Up to the depth of four 

 inches, soil fungi are fairly uniformly distributed. In deeper regions, 

 below four inches, no viable fungous spores seem to be present. There 

 does not seem to be any variation of fungi in regard to cultivated or 

 virgin soil. The climate seems to have great influence on the flora of 

 soil fungi. Species of Aspergillus are the dominant soil fungi of the 

 South ; FenicilUi, so freijuently found in northern States, are rare in 

 Texas soils ; tlie Mucorales are not as abundant in southern soils as 

 they are in colder climates. Pathogenic fungi, such as Fusarium, live 

 in the soil as saprophytes throughout the winter. 



Diseases of Plants. t — J. J. Taubenhaus had his attention directed 

 to a serious disease of the garden Columbine, which on examination 

 proved to be attached by the fungus ScUrotinia libertiana. The disease 

 is characterized by a general wilting of the leaves, the stems are 

 covered with a webwork of white fungus strands, and sclerotia are 

 lodged in the hollow centres. Cultures were made and the ascospore 

 stage was formed. The sclerotia may pass the winter in manure. 



F. L. Stevens and Alvah Peterson + describe some fungi that cause 

 disease on strawberries : Sphseroiiemella Frag arise sp. n., attacks the berries 

 and the affected spots become tan-coloured. The berry begins to shrivel 

 and in a few days is destroyed. The disease is not only injurious in 

 itself, but it is generally followed by more destructive fungi, such as 

 PJiizopus, which gain entrance through the lesions. Another fungus, 

 Patinella Fragarise sp. n., which forms sporodochia, is at first visible as 

 small sunken discoloured spots on the green or ripe strawberry, and 

 develops rapidly. Spores are produced in enormous numbers, and with 

 these cultures were made and fresh berries were successively inoculated. 

 Other diseases, such as Botrytis cinerea, Sphaeropsis malorum, and 

 Rhizopus nigricans, were noted as causing troul)le. 



A Sclerotinia% disease of Citrus called "cottony rot" attacks the 

 twigs of oranges and lemons in the orchard and the fruit of the lemon 

 in the packing house. Clayton 0. Smith has proved by his cultures 

 and inoculations that it is probably identical with Sclerotinia libertiana. 

 The hyphas of the vegetative stage are able to enter and destroy a 

 perfectly sound lemon without any abrasion of the skin, but attempts 

 to infect with spores were unsuccessful, except at the stem and 

 blossom ends. 



* Phytopathology, vi. (1916) pp. 241-53. 

 t Phytopathology, vi. (1916) pp. 254-7 (2 figs.), 

 t Phytopathology, vi. (1916) pp. 258-66 (1 pL). 

 § Phvtopathology, vi. (1916) pp. 268-78 (5 figs.) 



