May 19, 1922] 



SCIENCE 



547 



atmospheric temperature seven degrees lower in 

 summer than the cleanly cultivated orchard. 

 Humidity and evaporation records revealed 

 equally valuable data in that the humidity of the 

 cover-cropped orchard for a period of six months 

 was 12.44 per cent, greater and the evaporation 

 33 per cent, less than the cleanly cultivated 

 orchard. These temperature, humidity and evap- 

 oration relationships have a distinct economic 

 bearing in suggesting the avoidance of cover 

 crops in citrus orchards during winter as a means 

 of preventing cold injury, and in indicating the 

 value of such crops in equalizing the environ- 

 mental factors of the citrus plant. 



Physical and chemical factors in the growth of 

 asparagus: E. B. Working. Observations on the 

 great asparagus plantations of the Sacramento 

 islands were brought to bear on the particular 

 problems being studied. Cliarts shown included 

 growth curves illustrating particularly the rela- 

 tion of temperature to growth rate. Reactions to 

 chemical environment, as indicated by hydrations 

 under the MacDougal precision auxograph, were 

 discussed. 



Distribution of Arizona wild cotton (Thurberia 

 thespesioides) : H. 0. Hanson. A summary of 

 all information on distribution and abundance of 

 the wild cotton and the wild boll weevil. Present 

 knowledge shown to be inadequate. (Paper will 

 be published as a bulletin of the Agricultural 

 Experiment Station of the University of Arizona. ) 



The native wild cotton bollworm, Thurberiphaga 

 catalina Dyar, and its relation to cotton cultiva- 

 tion: C. T. VOBHIES. The Thurberia bollworm 

 is the larva of a native noetuid moth, recently 

 described, and known only in Arizona wild cotton, 

 Thurberia thespesioides. In its larval stages it 

 is a destructive bollworm of wild cotton. A 

 study of its life history now in progress has 

 shown that it can complete its larval life in the 

 bolls of cultivated cotton and it is therefore a 

 potential pest of that crop. Further observations 

 will be made to determine its adaptability to field 

 conditions of cultivated and irrigated laud. Re- 

 striction of cotton cultivation to areas non- 

 adjacent to wild cotton is a desirable precaution. 



Some observations of alfalfa girdle: . Feed- 

 EKICK Gibson. A disease of economic importance 

 to alfalfa growers of the Southwest, which was 

 first noticed and recorded in 1909, by Freeman 

 and McCallum. No description of symptoms have 

 been previously published. Osborn mentions a 

 girdle of alfalfa, due to a Membracid {Stricto- 

 cephala sp.). The complete paper with illustra- 



tions has been accepted by the Phytopathology 

 publishers and will soon be distributed. 



The use of cat tail (Typha latifolia) as a feed: 

 L. E. Feeudenthal. In a feeding experiment 

 with forty Duroc-Jersey pigs the writer demon- 

 strated on his own farm that cat- tail {Typha 

 latifolia) is a satisfactory feed. Its feed value, 

 composition and possible economic importance are 

 discussed. 



Suppression of molds during the incubation of 

 certain parasitic fungi: R. A. Studhalter. The 

 suppression of molds during the incubation in a 

 saturated atmosphere of certain parasitic fungi 

 in vitro may be accomplished by treating with 

 certain chemicals. Powdered sulphur,, various 

 concentrations of mercuric chloride, formaldehyde 

 and copper sulphate, and the use of a dry atmos- 

 phere are effective during the incubation of 

 Festalozzia sp. on the needles of Finns radiata, 

 particularly if the chemicals are applied after 

 one to four days of presoaking of the infected 

 needles in water. In the controls the molds ap- 

 peared to the unaided eye more than five days 

 before the Pestalozzia tendrils were pushed 

 through the ostioles; after the treatments men- 

 tioned, this advantage of the molds was reduced, 

 the tendrils appearing after some of them from 

 one to five days before the molds. The mycelial 

 growth of the molds was also retarded to a 

 greater extent than was the development of the 

 Pestalozzia. No chemical or treatment was found 

 which is able to suppress the molds without seri- 

 ously hindering the proper development of 

 Lophodermium sp. on the needles of Finns radiata, 

 in part probably because the open and more ex- 

 posed fruiting body of this fungus permits the 

 easy and rapid penetration of toxic agents. 



All undescribed fungus on the pepper tree: 

 J. G. Brown. The pepper tree {Schinus molle) 

 grown as an ornamental in the warmer parts of 

 the Southwest, is attacked by a fungus which 

 causes extensive rotting of the wood, eventually 

 resulting in death. Symptoms are gradual death 

 of the branches, or sudden death of the entire 

 tree preceded by wilting. The latter symptom is 

 likely to occur during the hot dry summer 

 months. It is due to the growth of the mycelial 

 hypha? in the trachese. In the case of gradual 

 death of the branches, sporophores appear on the 

 trunk or on branches during the summer rainy 

 season. The sporophores are bracket-like, brown 

 to almost black, azonate, annual, and they usually 

 have a maximum breadth of 12 to 15 cm. The 

 pores are hexagonal to subcircular, occasionally 



