December 12, 1913] 



SCIENCE 



857 



carefully studied. In general, it may be said 

 that the authors hold that fermentation of 

 lactose broth, or lactose bile, may be regarded 

 as a sufficient working test for organisms of 

 intestinal origin. If this idea is carried out 

 it will greatly simplify the routine procedure 

 in the examination of water. The work of 

 the English bacteriologists is discussed at 

 length, particularly that of Houston in Lon- 

 don and Clemesha in India. 



A new chapter has been added to the book on 

 the bacteriological examination of sliell-fish, 

 and it includes the recommendation of the 

 Committee on Standard Methods for the Bac- 

 teriological Examination of Shell-fish of the 

 American Public Health Association. The 

 appendix describes the preparation of culture 

 media, and contains an excellent list of refer- 

 ences. 



George C. Whipple 



SPECIAL ARTICLES 



THE CHESTNUT BARK DISEASE ON" CHESTNUT 

 FRUITSl 



Since the chestnut bark disease has been so 

 widely studied by the many investigators who 

 have given attention to it within the last few 

 years, numerous articles have been published 

 calling attention to the various ways by which 

 the infection is known definitely to be spread 

 from place to place, as well as of some meth- 

 ods that have been assumed to contribute to its 

 spread. The most prominent of those thus far 

 mentioned have been due to the transportation 

 of spores through the agencies of wind, rain, 

 insects, birds, rodents, man, etc., or to the 

 transportation of various fruiting and vege- 

 tative parts, or fragments of the fungus, by 

 means of infected cordwood, poles, ties, bark, 

 grafting scions, nursery stock, etc. So far as 

 the writer knows, no one has called special 

 attention to the danger of the disease being 

 transmitted by means of infected chestnut 

 fruits, yet infected nuts at times undoubtedly 

 are capable of spreading the disease, as will be 

 realized from what follows, which describes 

 one case which has come to our notice. 



1 Published by permission of the Secretary of 

 Agriculture. 



In September, 1912, Professor R. Kent 

 Beattie, Dr. T. C. Merrill and the writer 

 found numerous nuts and burs, which had 

 been lying on the ground in Lancaster county, 

 Pennsylvania, for several months, upon which 

 were many reddish brown pustules, in a buff 

 or yellowish mycelium. These looked very 

 much like the pycnidial pustules and myce- 

 lium of Endoihia parasitica. Portions of the 

 diseased fruits were inoculated by the writer 

 into the bark of a grafted Paragon chestnut 

 tree, while for comparison some inoculations 

 were made at the same time from a tyisical 

 canker. The infected nuts were collected on 

 September 4, 1912, and the infected bark was 

 collected and the inoculations made on the 

 following day. The records and results of 

 these inoculations are given below. 



The limb selected for inoculation was 

 healthy-looking, apparently free from disease, 

 from one to two inches in diameter, but on a 

 tree that was already diseased on some other 

 limbs. Eighteen cuts through the bark were 

 made with a sterile knife-blade, except as 

 noted below in the case of two cuts. For con- 

 venience in referring to these cuts they have 

 been numbered consecutively from 1 to 18. 

 Nos. 1, 2, 5, 6, 7, 8, 11, 12, 13, 14, lY and 18 

 were checks, all uninoculated in the ordinary 

 sense, though cuts 13 and 14 were made with 

 the knife-blade after it had been used to cut 

 some of the infected bark to be inserted in cuts 



15 and 16. 



Cuts 3 and 4 were inoculated with pieces of 

 the mycelium-covered shell of the nut after the 

 pustules had been cut away ; cuts 9 and 10 were 

 inoculated with pieces of the shell to which 

 pustules were still attached; and cuts 15 and 



16 were inoculated with pieces of bark from a 

 disease lesion on the bark of an American 

 chestnut tree. 



On July 22, 1913 (about ten and one half 

 months after the inoculations were made), the 

 inoculations and checks were reexamined and 

 records made of their condition. Cuts 1 and 2 

 were uninfected. Cut 3 likewise was unin- 

 fected. Cut 4 had developed a characteristic 

 lesion about 4 inches long. Cut 5 was sur- 



