JULT 9, 1909] 



SCIENCE 



61 



dance, but not anywhere on the surface of 

 the plant except at its base. The mycelium 

 extended upward inside this stem two thirds 

 of its length. On another plant in this pot 

 Diplodia was also found in fruit on the crown, 

 and the mycelium was present in the interior 

 of the stem but did not extend upward for any 

 distance. 



On the same day in another pot the my- 

 celium was found in the parenchyma and 

 bundles of the roots of one plant. Pieces of 

 the roots were put into damp chamber and in 

 five days the pycnidia of Diplodia appeared 

 in great numbers. 



The same day in a third pot the mycelium 

 of Diplodia was found not only in the interior 

 of the roots but also in the interior of the 

 first two internodes of the stem, from which 

 pure cultures of it were obtained. Here again 

 it was not present on the surface. 



The nest day in a fourth pot Diplodia was 

 found fruiting on the stem in the first four 

 internodes as a result of the presence of in- 

 ternal mycelium. This mycelium was also 

 demonstrated in the interior of the fifth in- 

 temode, and pure cultures of it were obtained 

 from the interior of this stem. Generally 

 the pycnidia were most abundant at the nodes. 

 They occurred also on the leaf sheaths. 



The following summer (190S) the experi- 

 ment was repeated in a plot out of doors by 

 means of soil inoculation with pure cultures, 

 but, owing to a late start and the fact that 

 the plants had to be dug up early to make 

 room for a new building, the experiment was 

 a failure, except that there were indications 

 of infection in the basal nodes and inter- 

 nodes of two plants. Experiments are under 

 way again this summer. 



There seems little doubt that the manner of 

 infection indicated is the common one, i. e., 

 from the soil into the roots, from these to 

 the interior of the stems, and thence upward 

 to the cobs, and finally to the kernels, but it 

 is not unlikely that certain soil conditions 

 may favor or hinder the root infection. This 

 remains to be worked out. Unquestionably 

 the Diplodia, like the Fusarium, is a soil or- 

 ganism persisting from year to year in in- 

 fected fields, which for this reason should be 



staked off and planted to other crops than 

 corn. 



It is also worthy of inquiry whether this 

 fungus may not be the cause of the so-called 

 " cornstalk " disease prevalent among cattle 

 in the west. It is also possible that to Diplodia 

 should be referred the great numbers of 

 deaths of negroes in the south during the 

 past three years from the so-called pellagra, 

 following the consumption of moldy corn- 

 meal and moldy hominy. This fungus 

 (Diplodia) is also a cause of moldy corn in 

 Italy. The only other fungi we have reason 

 for suspecting in this connection are species 

 of Aspergillus. The writers would be very 

 glad to receive for study samples of hominy 

 or corn meal suspected of being the cause of 

 pellagra. 



Erwin F. Smith, 

 Florence Hedges 

 Labobatory of Plant Pathology, 

 Bureau of Plant Industry, 

 Department of Agriculture, 

 Washington, D. C, 

 July 23, 1909 



SOCIETIES AND ACADEMIES 



THE GEOLOGICAL SOCIETY OF WASHINGTON 



At the 218th meeting of the society, held at the 

 Cosmos Club, on Wednesday evening, April 14, 

 1909, Mr. David White presented as an informal 

 communication some notes on the " Kent Coal 

 Basin of Southern England." Calling attention 

 to Professor E. A. Newell Arber's paper in the 

 February number of the Journal of the Geological 

 Society of London, in which the fossil plants from 

 the deep drillings near Dover, England, are de- 

 scribed, he pointed out that the three workable 

 coals, 1,881-2,377 feet deep in the Waldershare 

 core, are paleobotanioally either Mercer or Clarion 

 in age, probably the former, though both ages may 

 be represented. The boring about 6 miles farther 

 south, on the coast, cuts 13 coals between 1,100 

 and 2,270 feet, in a more arenaceous series, also 

 of older Pennsylvanian age. The drillings there- 

 fore indicate a considerable number of workable 

 coals in the basin (Kent) passing beneath the 

 Channel at Dover. 



Regular Program 

 Debris Trades on the Domes of the Tosemite 

 Region: Mr. F. E. Matthes. 



