June 30, 1922] 



SCIENCE 



707 



Great Falls, Va. ; Tallulah, La. ; Houston, Tex. ; 

 Chesterville, 111. ; near Decatur, 111. 



Proturans have been searched for but not 

 found in the following localities: Vicksburg, 

 Miss.; Dallas, Tex.; Ames, la.; Toronto, Can. 

 In addition, also, Professor Silvestri has 

 looked for them at Ithaca, N. Y., without find- 

 ing any. 



The known distribution up to date of Pro- 

 turans in the Nearctic is shown by the accom- 

 panying figure, each positive record being 

 indicated by a large dot and each negative 

 record by a question mark. 



It would be premature at this time to attempt 

 any generalizations in regard to the Nearctic 

 distribution of these most primitive hexapods, 

 yet by way of summary it may be noted that 

 up to the present Proturans have been found 

 in 9 localities in the Upper Austral Life Zone, 

 these records coming from 4 different states; 

 from 2 localities in the Lower Austral Life 

 Zone, the records being from different states; 

 from 1 locality in the Transition Life Zone. 

 Of the negative records, 1 is from the Upper 

 Austral, 2 from the Lower Austral and 2 from 

 the Transition. 



The only life zone in which these hexapods 

 have been found in either abundance or 

 diversity is the Upper Austral. In the Lower 

 Austral only two minute under-bark species 



The known distribution of Nearctic Proturans. 



were taken — two specimens of .Eosentomon 

 pallidum Ewing from Tallulah, La., and two 

 specimens of Eosentomon minimum Ewing 

 from Houston, Tex. In the Transition, three 

 specimens of Eosentomon wheeleri Silvestri 

 and one specimen of Eosentomon pallidum 

 Ewing were taken from decaying leaves and 

 twigs near Bluemont, Va., at the top of the 

 Blue Ridge Mountains (elevation 1,200 feet). 

 H. E. Ewing 

 U. S. National Museum 



STEM END ROT OF APPLES 

 During the late spring of 1921 a large 

 number of apples were found which developed 

 a decay at and around the base of the stems. 

 These apples were in a lot that had been re- 

 moved from a cold storage , temperature of 32° 

 and held for a few days at 45° Pahr. When 

 placed in moist chambers such apples very 

 soon decayed without wrinkling, becoming soft 

 and watery. The decay was of a sharply de- 

 fined nature, such that the affected parts could 

 te easily removed. Normally these decayed 

 apples were soon covered with green mold. On 

 examining the stems of apples in storage it 

 was found that many stems were green with 

 spores. Cultures of this mold were made by 

 the poured plate method. The fungus was be- 

 lieved to be Penicillium expansum Link., and 

 was later identified as such by Mr. Charles 

 Thom of the U. S. D. A., Bureau of Chemistry. 

 A search of the literature on apple decay 

 was made, but no mention of the entrance of a 

 decay-producing organism through the stem 

 was noted. The decay of apples ordinarily 

 caused by P. expansum is invariably mentioned 

 in connection with abrasions of the skin, such 

 as insect punctures, wounds or injuries of a 

 mechanical nature. Some writers mentioned 

 the infection as entering through the calyx or 

 blossom end but no one noted st€m end infec- 

 tion. 



The matter was taken up with Mr. E. A. 

 Siegler, assistant pathologist of the U. S. D. A., 

 Bureau of Plant Industry ; Mr. Charles Brooks, 

 pathologist, and Dr. Charles Thom, mycologist, 

 U. S. D. A., Bureau of Chemistry, none of 

 whom had noted such a decay gaining access 

 to the apple by way of the stem. In fact they 



