244 EXPERIMENT STATION RECORD. 



(E. S. II., 24, p. 549), in which apple troubles, beet leaf spot, cherry rot and 

 mildew, hop mold {Sphwrothcca humuli), frost injury to trees, pear troubles, 

 Rhizoctonia on potatoes, and raspberry cane blight are especially discussed. 



On the air infection of ergot and the dissemination of plant diseases by 

 means of temperature currents, R. Falck {Ztschr. Forst u. Jagdio., ^3 (1911), 

 No. 3, pp. 202-227, figs. 4). — The author discusses the influence of air and tem- 

 perature currents on the dissemination of fungus spores in general, and of 

 Claviceps in particular, under 3 headings, viz (1) the spore discharge from the 

 ascus, (2) the further distribution of tlie discharged spores by temperature 

 currents, and Ci) the infection of rye by wind-blown ascospores of C. purpurea. 



On the mechanical measurement of the resistance of grains to disease, 

 F. Stkanak (Deut. Landw. Prcsse, 38 (Idll), No. 18, pp. 209, 210, fiy. 1).— 

 The author figures and describes an instrument for determining the strengtJi 

 and hardness of the cuticle and outer layers of the stems of grains. By this 

 method it is claimed that a fairly accurate estimate of the disease resistance 

 of various species and varieties of grains can be obtained. 



On the longevity of barley loose smut (Ustilago hordei) in infected seed, 

 H. ZiMMERMANN (ZtscJir. Pflanzenkrank., 21 {1911), No. 3, pp. 131-133).— 

 The results are given of planting 1, 2, and 3 year old barley seeds from plants 

 which had been exposed to loose smut infection. 



It was found that the seeds of susceptible varieties of barley which were 

 smut infected when planted gave smutty ears, whether planted the first, second, 

 or third year. It thereby showed that the smut mycelium in the barley grain 

 can survive a three-year period of rest and, when subjected to the proper con- 

 ditions for growth, may develop and produce smutty barley heads. 



The influence of bunt on the shape of the wheat head, K. Miczynski 

 (Ztschr. Landw. Versuchsw. Osterr., U (1911), No. 3, pp. 232-23.'t, fig. 1).— 

 Attention is called to the elongation of the heads of wheat attacked by stink- 

 ing smut, in which the diseased heads are nearly twice the length of normal 

 healthy ones. 



Is Neocosmospora vasinfecta the perithecial stage of the Fusarium which 

 causes cowpea wilt? B. B. Higgins (North Carolina Sta. Rpt. 1909, pp. 100- 

 116, figs. 16). — The author gives the results of a series of cultures on various 

 media of the cowpea wilt organism, F. vasinfectum, obtained from the interior 

 of diseased cowpea vines, and of N. vasinfecta obtained from the exterior of 

 cowpea stems which had been killed by the wilt. 



The Neocosmospora cultures were made from perithecial material and were 

 grown on several different culture media and for several generations, includ- 

 ing pure mycelial, conidial, and ascosporic cultures all from one original 

 perithecial culture. 



The internal Fusarium cultures were obtained by aseptic transferi'ence of 

 the mycelium from inside the stems to plates of cowpea-leaf agar. The 

 ascigerous fungus (N. vasinfecta) showed the following characters: Peri- 

 thecia always present; mycelial growth slow, never pure white, scanty, and 

 usually strict; macroconidia and chlamydospores never present; bright colors 

 (red, yellow, pink, or purple) not produced in any substratum; yellow spore 

 clusters absent; and growth not occurring below the surface of the gelatin. 

 On the other hand, the internal fungus (F. vasinfectum) showed perithecia 

 never present ; mycelial growth rapid and profuse on rich media, aerial, floc- 

 cose, and on most media, pure white ; chlamydospores present in all old cultures ; 

 bright colors produced on starchy foods; yellow spore clusters developed on 

 agar, potato, and stems of cured cowpea hay ; and growth produced below the 

 surface of the gelatin. 



