]Mr. ^^'ooDS on the Genera of European Grasses. 3 



grasses. Later still, Kunth in liis valuable work on the Gramineœ has ar- 

 ranged all these with Trlticum, while the annual small-seeded Tritica, which 

 had been united by some authors to Braclii/podinm, are referred by him to 

 Festuca. He has also referred to Festuca the Sclerochloa of P. de Beauvois, 

 some of whicli are plants which Smith had separated from Poa to add to Gli/- 

 ceria, and he leaves to the latter genus only two European species, G.fluitans 

 and G. aqnatica, plants not in habit closely allied, yet certainly very similar 

 in the structure of their florets. 



The number of genera of grasses described by Kunth is 235, embracing 

 3034 species. No one can have all these at once present to the mind, and it 

 therefore becomes necessary to adopt some method which may bring them 

 before us in regular succession or in tribes. Linnaeus founded his primary 

 divisions on the number of florets in a common calyx, and their arrangement 

 in a scattered manner, or in a regular spike, making some exceptions, and 

 adding in one or two instances some other character, in order to avoid any 

 violent opposition to nature. His system obliged him to disperse some genera 

 into different classes ; but in those included in the class and order Triandria 

 Digynia he has endeavoured, in numbering the genera, to show something of 

 their natural afhnities in a consecutive series. In the English Flora, where 

 the genera are less numerous, it appears of less consequence to make a com- 

 plete arrangement ; but Sir J. E. Smith has followed the example of Linnœus 

 in a double distribution, arranging the genera at first according to a definite 

 character, and when he comes to the species, placing them in an order more 

 nearly corresponding with their natural affinities. No art, however, can 

 reduce the genera of grasses into a simple natural series. The Liiniean bo- 

 tanists of the continent of the present day do not seem in general to trouble 

 themselves with this double order, but are contented to number and place 

 the genera as they are distributed by the artificial character, and in this they 

 have been followed by Dr. Hooker. Palisot de Beauvois, observing the de- 

 fects of all former arrangements, published in 1812 an "Essai dhme Nou- 

 velle Agrostogriiphle." In this he divides the grasses into two great families, 

 in tlie first of which the spiculae or locustae are all alike, each containing 

 either perfect florets, or florets which unitedly contain all the parts necessary 

 for the reproduction of the plant. Tlie second contains those plants where 



B 2 



