2 6 THE NA Tl 'RES TUB Y RE VIE IV [a : ,_, AM , ARy , Ig0 6 



only beginning nature-study will find the interest of the work greatly 

 enhanced by the formation of a similar habit of alertness regarding 

 presentations which are likely to throw light upon problems previously 

 met with in experience. For example it has been pretty well estab- 

 lished that as a rule in forest growth conifers come in early and for 

 years require shelter which is afforded them by herbaceous trees. It 

 has also been observed that seeds of willows and poplars are light and 

 are blown far by the wind, that the red cherry seed is edible and is 

 carried by birds, that acorns are hoarded by squirrels and mice, and 

 that water washes up many varieties of seeds. 



In our investigation we found constant verification of these and 

 other well known theories. A striking illustration of the fact that 

 seeds may be unintentionally disseminated by commerce was afforded 

 by the appearance of dandelions only in places where packing boxes 

 had been opened. 



The narrow limits of such a paper will not admit of further reference 

 to the more fascinating and productive studies of structure, function 

 and life-relations. The interest in such work is always cumulative, 

 the nature-study attitude soon becomes habitual and after that all is 

 clear sailing. 



A SIMPLE EXPERIMENT ON SPONTANEOUS GENERATION 



BY F. L. STEVENS 

 Professor of Botany and Bacteriology in North Carolina College of Agriculture and Mechanic 



Arts 



One of the greatest controversies of the world, one freighted with 

 results of the utmost importance to mankind, was the controversy over 

 the spontaneous generation of micro-organisms which was at its height 

 in the fifties and sixties of the last century. Decline in the belief of 

 spontaneous generation from earliest ages to that time had been con- 

 stant. The Aristotelian belief in the generation of eels from the mud 

 of the Nile, and the early grotesque belief in the ability of foliage of 

 certain trees to change into mammals, fishes, and bird-; had given way 

 under the searching criticism of later observers. Finally even the 

 spontaneous generation of maggots was disproved by the Italian Redi 

 (1629-97), and their origin from eggs laid by flies demonstrated. 



With the discovery of micro-organisms — bacteria, yeasts, and the 

 like — the spontaneous generation controversy was reopened. While 



