DISEASES OF PLANTS. 247 



(E. S. R., 22, p. 648) relatiufr to flower infection by the fungus causing cotton 

 antlaracnose led the author to investigate (he subject at some length. lie claims 

 that infection of cotton bolls following flower inoculation can take place in either 

 of two ways. The system may grow saprophytically upon the dead flower parts 

 and finally grow through and into the boll, or it may cause the disease by grow- 

 ing dowTi through the pistil into the boll. The anthracnose probably follows 

 both methods, while the cotto*i bacterium (Bacterium malvaceanim) infects the 

 liolls through the first method. 



The author carried on a large number of inoculations in which he injected 

 organisms suspended in water into the flowers, and determined the infection. 

 More than half of the diseased bolls were attacked at the tip, while the per- 

 centage of infection along the lines of dehiscence was small. When the bolls 

 are small they are readily infected with anthracnose, though, so far as the 

 observations of the author go, no one part of the boll is more susceptible than 

 another. If is evident that the bolls may be infected through the flowers, but 

 the author claims that this is not the usual method of infection. 



Sclerotinia panacis n. sp. the cause of a root rot of ginseng, AV. II. Rankin 

 (Plnjtoixitholoo!/, 2 (1912). \o. 1, pp. 28-3J. pi. 1, flg. 7).— While investigating 

 the diseases of ginseng in 1000, the author became interested in the disease 

 commonly known as black rot (E. S. R., 22, p. 246). Subsequent investigations 

 showed a rather widespread infection, and specimens were collected and kept 

 in a culture chamber at ordinary room temperature, but no growth followed. 



In 1010 a further study was made and the perfect stage of the fungus dis- 

 covered. This differed from the species of Sclerotinia already described. 

 Primary infection of the roots seemed to occur at no regular place, as they 

 were found to start either at the crowns or in smaller roots. 



Control measures have not been definitely detei'mined, but the eradication of 

 affected roots and soil sterilization with formaldehyde or steam are rec- 

 ommended. 



A technical description of the fungus. .9. panacis n. sp., is given. 



Infection experiments with potato fungi, H. W. Wollenwebeb and O 

 ScHLUMRERGEB (Mitt. K. B'tol. Aust. Land. u. Forsttv., 1911, No. 11, pp. 15-17; 

 ohs. in Centhl. Bald. [etc.'\, 2. Abt., 32 (1912). No. 6-12, p. 315).— The authors 

 infected tubers with spores of Verticilliuni alboatnim, Fmsohmj/j solani, F. 

 cccrulcum, F. orthoceras, F. subitlatum, and F. discolor by means of the Pravaz 

 spray. 



It was found that the spores of F. coerulciim and F. solam germinated in 

 part and caused in isolated cases a slight rotting which did not extend to the 

 whole tuber in any case. The other infections gave negative results. Xo 

 decisive results were obtained by infection of stems and roots with the spores 

 of the fungi named. 



The natural distribution of Fusaria on the potato plant, H. W. Wollen- 

 WEBEB (Mitt. K. Biol. An^t. Land u. Forstic, 1911, No. 11, pp. 20-23; ahs. in 

 Centhl. Bakt. [etc.], 2. Aht., 32 (1912), No. 6-12, p. 326).— The author states, 

 as the result of his investigations, that Fusarium subulatum and F. dimerum 

 are the most common forms, attacking all organs of the host plant. The former 

 is said to be almost omnivorous. It is found late in August in the stems which 

 remain green, as is true also of Verticilliiim alboatrum. Those which occur 

 most comraonly on the tubers are F. solani, F. martii, F. coenileum, and F. 

 discolor sulphureum. 



Leaf roll of potatoes, O. Appel and O. Schlumbebgeb (Mitt. E. Biol. Anst. 

 Land u. Forstw., 1911, No. 11, pp. 13-15; ahs. in CentU. Bakt. [etc.], 2. Abt., 

 32 (1912), No. 6-12, pp. 321, 322).— The authors investigated the statement 

 that enlargement of the mother tuber is a characteristic of potato plants 



