MB. G. BENTHAM ON GEAMINEiE. 27 



The long styles, moreover, would place the majority of the sub- 

 tribe Seslerie£B, for instance, among Panicacess, when all their 

 other characters are those of Poacese ; and the species are very 

 numerous in which, from the intermediate length of the styles, 

 or from both the lower smooth part and the stigmatic portion, 

 or the lower part alone, being described as styles, they are 

 differently characterized as long or short by different writers. 



Pournier rejects both Brown's and Pries's primary divisions, 

 but proposes a new one founded on the position of the lowest 

 glume of the spikelet, next to the main axis in Chlorideas and 

 Hordeacece, and averted from it or external in other tribes. But, 

 in the first place, this relative position cannot well be ascertained 

 in loosely paniculate G-raminesB, where there is so frequently a 

 slight, almost imperceptible torsion of the pedicel, and, in the 

 next place, in one-flowered spikelets it is often uncertain which 

 is to be regarded as the lowest glume. The total number of 

 glumes in the tribe Panicese, for instance, is variable, according 

 to the genus or section, two, three, or four; the lowest in 

 Eeimaria, and in a few species of Paspaliim, corresponds to the 

 second in the majority of Paspala and a few allied genera, and to 

 the third in Panioum. All these genera are included by Pournier, 

 as by all others, in one and the same tribe ; and if so, are we to 

 regard as the outer glume the small outer one of Panicum, called 

 by some an extra bract, and an imaginary one in Paspalum and 

 its allies, or the outer one of Paspalum, which is second in Pani- 

 cum ? Again, in one and the same genus, the relative position of 

 the outer glume and the main axis is not always constant, as, for 

 instance, in Paspalitm, in Nees's section BigitaricB {JSmprosthion, 

 Doell, Anastrophus, Schlecht.), the outer glume and the flowering 

 one above it are external, whilst in the majority of the genus 

 they are turned towards the central rib of the main axis, and 

 yet the two groups are not distinguished by Pournier even as 

 sections. 



Another character much insisted on of late years for tribual 

 distinction is still more uncertain, the adherence of the ripe grain 

 or caryopsis to the palea, as in Festuca, Bromus, &c. This is 

 usually very 'conspicuous in the dry state, although even then 

 the grain is often only closely embraced by the palea, and when 

 moistened the adherence very generally disappears. The union 

 of the two is perhaps never truly organic, and in hot water I 

 have always found them readily separable without any tearing. 



