468 EXPERIMENT STATION RECORD. 



leaves was investigated by Stahl's cobalt chlorid test. It was found 

 that pear leaves attacked by Fusicladium pyrinnm aud apple leaves 

 attacked by F. dendrUicum transpired from both surfaces of the dis- 

 eased areas more thau the normal amount, while pear leaves infected 

 with SplHvreUa sentiua were found to transpire no more from the dis- 

 eased spots thau from equal areas of the sound leaves. 



Strawberry leaves attacked by Sphcerella fragaruc were found to have 

 their transpiration reduced. 



Grape leaves, showing the presence of Peronospora viticola, gave no 

 transpiration from the diseased areas, while the sound portions trans- 

 pired as usual. The reason for the the checking of the transpiration 

 is supposed to be due to the formation of conidia, the stomata being 

 closed by the conidiophores. 



The effect of fungi in leaves, upon their activity in starch and sugar 

 formation, was investigated, and it was found that the young s^iots con- 

 taining Fusicladium were free from starch, while the surrounding cells 

 contained it in abundance. The cells in the Peronospora spots were 

 without starch, as were the surrounding cells in the sound tissue, the 

 area extending for several millimeters. The author ascribes this lack 

 of food material to the action of the parasite, the starch, etc., having 

 been withdrawn from the surrounding cells. 



The adaptability of tubercle bacteria of unlike origin to differ- 

 ent genera of Leguminosae, F. Nobbe and L. Hiltner [Landic, 

 Vera. Stat., 47 {1896), Xo. 4-5, j^P- 257-268, pU. 6). — The experiments here 

 reported were made in continuation of those given some 2 years ago,^ 

 and consisted in inoculating 10 genera representing 6 different tribes 

 of leguminous plants with pure cultures of bacteria from the tubercles 

 of Phaseolus multijforus, risiim sativum, TrifoUum pratcnse, Rohinia 

 pseudacacia, and Lupinus lutens. The' plants were grown in x^ots con- 

 taining 1,200 gm. of air-dry garden soil, with a nitrogen content of 3.45 

 gm., and 0,800 gm. of pure quartz sand. P^ach pot was given as 

 additional fertilizer 500 gm. potassium chlorid and 5,000 calcium 

 phosphate. Eecords were compiled for each experiment and the results 

 tabulated, showing the analyses of the plants grown with the different 

 inoculations. It was shown that as a rule there could be no substitu- 

 tion of bacteria from one kind of legume for another except within nar- 

 row limits, the best results being secured when each plant had received 

 an inoculation with its specitic organism. 



It was further shown by these experiments that: 



"(1) The tubercles exert no iufluence upon the aerial parts of the 

 plant so long as the supply in the soil furnishes nitrogen in sufficient 

 quantity. 



"(2) From the time when the nitrogen begins to fail, plants without 

 tubercles or having poorly developed ones can not supply the required 

 nitrogen, the leaves of legumes in no sense being organs for the assim- 

 ilation of free atmospheric nitrogen." 



'Landw. Vers. Stat., 45 (1894), pj). 1-27 (E. S. R., (i, j). 504). 



