26 ME. 6. BEHTHAM ON GEAMINE^. 



imperfection is in the lower flowers of the spikelet ; and Poacete, 

 in which the tendency is in the opposite direction. This indica- 

 tion of the principle kept in view is too indefinite to serve as a 

 practical character; but, combining it with that proposed by Munro 

 of tlie articulation in the axis of the spikelet being below the 

 spikelet itself (in the pedicel) in Panicacese, and above the lowest 

 glume or none in Poacese, the exceptional forms are reduced 

 to the lowest possible figure. This primary division, although 

 tacitly approved of by many partial agrostologists, has not been 

 generally adopted in systematic works, and many attempts have 

 been made to divide the Order according to more positive cha- 

 racters, but as yet with but little success. 



Kunth entirely gave up Brown's primaiy groups and divided 

 the Order into thirteen tribes, many of which were natural, 

 fairly deiined by a combination of characters, and bare been very 

 generally adopted. Others have been objected to on various 

 grounds. He attached too much importance to such characters 

 as the separation of the sexes or the increase in the number of 

 stamens, which are exceptional in different groups rather than 

 tribual distinctions ; in the general arrangement, his removal of 

 the Andropogoneae to a distance from the Panicese is disapproved 

 of; and his describing flowers as actually existing when only theo- 

 retically imagined is sometimes misleading. Nees generally 

 adopted Kunth' s tribes, but improved the circumscription of 

 some of them, and added two or three small ones. Trinius never 

 completed his revised arrangement of the Order. Since the time, 

 however, of these great agrostologists, systems have been sketched 

 out which require a few words of notice. 



Pries, followed by Andersson, proposed for a primary division 

 of Graminese that into CliscmtJiece, with the flower («. e. the 

 flowering glume and palea) closed and the elongated styles pro- 

 truding at the apex, and JEuryantTiece, with the glume and palea 

 open at the time of flowering and the short styles protruding 

 laterally. This division is, however, practically useless, except 

 perhaps for the limited number of species that can be observed 

 in a living state. The flowers of most species open only for a 

 very short time, and in dried specimens are almost always closed. 

 The styles, again, are in many cases so exceedingly slender and 

 fugacious as to be very difficult to observe in dried specimens, 

 except in the bud, when they have not yet attained their full 

 development, or after fertilization, when they are withering away. 



