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season. The writer of tlie article entitled as above gives the names 

 of several authors, the results of whose experiments go to prove 

 that those plants exposed through natural causes to a low tem- 

 perature during their period of rest, as well as those artificially 

 exposed, being placed on ice, when given again the conditions of 

 growth develop earlier and faster than others whose winter rest 

 has been passed under a higher temperature. Similar experi- 

 ments have been tried with seeds, proving that seeds of certam 

 grains grown in an extreme northern climate, when planted m 

 warmer climates, develop seeds again in less time than those 

 grown in the same warmer cUmate. These results, the author 

 thinks, do not imply with any degree of certainty that the climate 

 is the only factor concerned. The seed of the colder climate may 

 have acquired certain characteristics from a long series of genera- 

 tions, Instead of the single seed being affected by the climate of 

 the winter it has passed through. Other experiments touching 

 this latter part of the question have been carried on in St. Peters- 

 burg also by Haberlandt. Seeds were exposed to cold after 

 having been swollen by absorption of water. After being exposed 

 some time to a temperature of I7°5, (Celsius) they were allowed 

 to thaw very gradually. Plants obtained from seeds so treated, 

 all other conditions being equal, produced blossoms a few days 

 earUer than those not so treated. The author tried similar 

 experiments with somewhat different results. Seeds from eight 

 different species were taken, divided in three sets, each set treated 

 differently from the other two in respect to the degree of cold 

 they were exposed to during their winter rest. They were not 

 swollen by placing in water, but were simply kept during the 

 winter in rooms of different temperature: one set in a room of 

 about 19^ or 20°; another where it varied from 1° to 24"^; the 

 third exposed to all the rigors of a Berlin winter, not, however, 

 allowed to be in contact with snow or ice. These seeds, in the 

 spring, were given the same conditions. The plants obtained 

 from the three sets showed no difference, either in time of germi- 

 nating or of flower and seed producing. The question is one of 

 strong practical interest as well as scientific. In both directions 

 it seems well worth taking up, especially as so little compara- 

 tively has been done with it E- L- G. 



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