THE AMERICAN BOTANIST 113 



colonies of rare plants. In all broken country this condition 

 exists ; the prairie flora, is the one that is on the way to exter- 

 mination. Already a piece of native prairie is hard to find and 

 the flowers are disappearing before the plow. 



Early Plant Names. — It is popularly supposed that 

 Linnaeus was the originator of the binomial system of naming 

 plants and the first botanist to give but two names, a generic 

 and a specific, to each species. This is quite incorrect. Two 

 centuries before the time of the famous Swede there were 

 writers on plants who knew them by only two names which 

 were clearly equivalent to genus and species. The good ex- 

 ample they set was not followed, unfortunately, and it re- 

 mained for Linnaeus to give this method sufficient promin- 

 ence and authority to make it accepted by later writers. Be- 

 fore the day of generic and specific names plants were com- 

 monly designated by a string of Latin words. Thus our com- 

 mon adders tongue (Erythronium Americanum) was called 

 "Dens caninus Hore luteo," the Christmas fern {Polystichum 

 acrostichoides) was "Filix mas foliis integris auriculatis," and 

 the walking fern {Camptosorus rhisophylliis) masqueraded as 

 Phyllitis parva saxatilis per summitates folii prolifera. The 

 wonder is that the world waited until the time of Linnaeus 

 for so manifest an improvement. 



Bacteria in the Soil. — Most people are fairly familiar 

 with the fact that the soil is by no means a mere collection of 

 dead and inert particles of sand and clay. Billions of bacteria 

 are found in every inch of the surface layers and the soil may 

 be said to be alive in the most literal way. Many of these bac- 

 teria are helpful species engaged in turning decaying vegeta- 

 tion into nitrates for the use of other crops, but others there are 

 in plenty that cause diseases in plants or animals. The bacteria 

 causing plant diseases are among the more interesting. In 



