708 



SCIENCE 



[Vol. LV, No. 1435 



doubted the possibility of any fungus travers- 

 ing the dry stem of an apple. It is well proven 

 that stem end rots occur in other fruits, for 

 example, the stem-end rot of citrus caused by 

 Phomopsis sp. and the stem-end rot of both 

 citrus and watermelon caused by two species 

 of Diplodia. 



In the fall of 1921, large, mature Yellow 

 Bellefleur apples were secured from trees in a 

 Berkeley garden. These apples were picked 

 with the fruit spurs attached, carefully washed 

 in wood alcohol, mercuric chloride solution 

 1-1000 and distilled water consecutively. The 

 leaves were clipped from the spurs to facilitate 

 the work but the spurs were not removed. 

 Moist chambers were sterilized, lined with filter 

 paper, washed out with mercuric chloride solu- 

 tion, rinsed with distilled water, glass covers 

 were prepared in the same manner. The spurs 

 were then removed from each apple in turn 

 and spores of P. expansum from sub-cultures 

 made from the original isolation were planted 

 on the freshly exposed surface at the ends of 

 the apple stems, and the apples placed in the 

 moist chambers. Control apples similarljr 

 treated but not inoculated were placed in jars 

 prepared in the same manner and all were 

 kept under the same conditions in the labora- 

 tory. Of the six apples treated in this manner, 

 four developed the characteristic stem end rot 

 and were soon completely decayed. The check 

 apples kept in good condition for three months. 



Yellow Newtown apples were picked in the 

 same manner at Watsonville, California, and 

 brought to Berkeley. On October 17, 1921, 

 three of the ripest of these apples were treated 

 and inoculated in the same manner as the 

 Bellefleurs. On November 18 the decay of all 

 three apples was identical with the decay ob- 

 served on the fruits naturally infected. Six 

 Yellow Newtown ajsples were treated in the 

 same manner and inoculated with the same 

 organism several days later than the previous 

 group and they all developed the typical decay. 

 In all eases the checks remained in good con- 

 dition. At the end of six weeks, all the apples 

 so inoculated were entirely decayed and covered 

 with green spores. 



Cultures of the spores appearing on the sur- 

 face of the inoculated apples were made and 



appeared identical in every way with the 

 original culture. Stab inoculations were made 

 with these re-isolated cultures on apples also 

 carefully sterilized. At the same time other 

 apples were inoculated with the original cul- 

 ture. The results were identical, the typical 

 Penicillium decay of apples resulting at every 

 puncture. A penicillium isolated during the 

 fall of 1921 from decaying prunes was found 

 to cause typical decay of apples when inocu- 

 lated into the iiesh. This prune penicUlium 

 was planted on three Yellow Newtown apple 

 stems and within three weeks it caused typical 

 stem end decay pf all three apples. This organ- 

 ism was later found to be identical in all of its 

 reactions with the original penicillium isolated 

 from apples. 



Washings made from the attached leaves on 

 some of the apples used in the experiments 

 were plated and tj^pical colonies of P. expan- 

 sum, appeared on all the plates so made. About 

 15 per cent, of the colonies which grew were 

 identified as some species of Penicillium, a con- 

 siderable number of which caused typical P. 

 expansum decay when inoculated into mature 

 apples. This would indicate the prevalence of 

 the organism in the trees at the time of harvest. 



These results prove that stem end infection 

 of apples is a possibility. Observations by 

 the writer indicate that this mode of infection 

 is quite common among the apples of this state, 

 especially in Yellow Newtowns. Though re- 

 tarded in cold storage, the rot makes some 

 progress at a temperature of 45° Fahr. and at 

 room temperature the decay is rapid. 



Clyde C. Barntjm 

 University of California, 



AMERICAN PHYSIOLOGICAL 

 SOCIETY 

 ' THIRTY-FOURTH ANNUAL MEETING 

 The thirty-fourth annual meeting of the 

 American Physiological Society was held during 

 the Christmas holidays under the patronage of 

 Yale Universitjr, New Haven, Connecticut. Two 

 scientific sessions daily were held December 28, 

 29 and 30. The meetings opened at 9:30, De- 

 cember 28, with a joint session of the societies 

 of the Federation of American Societies for 



