9 



lated below the empty glumes, the spikelets falling from 

 the pedicels entire, either singly, in groups, or together 

 with the joints of an articulate rachis. The first six 

 tribes belong to this series. 



This first grand division of the order Graminese is 

 based upon two characters in combination, the articu- 

 lation of the pedicels just below the spikelets or cluster 

 of spikelets and the single perfect flower, which may or 

 may not have a staminate or imperfect flower below it. 

 There are never more than four glumes in the spikelets, 

 the first three being empty or the third with a rudi- 

 mentaiy or staminate flower in its axil; the fourth 

 glume subtends the perfect or hermaphrodite flower. 

 In a few genera the spikelets are reduced to two or 

 even only one glume, but in these cases the articulation 

 of the spikelet with the pedicel below the outer glume 

 indicates its connection with this series. 



KEY TO THE TRIBES IX SERIES- PANICACE^. 



1. Spikelets usually much compressed laterally, 1-flowered; empty 

 glumes none or rudimentary; flowers staminate, pistillate, 

 or hermaphrodite Tribe VI. oryzeje. (See page 43.) 



1. Spikelets not compressed laterally, somewhat dorsally com- 



pressed or terete; empty glumes- two or three (one only in 

 Reimarhi) 2 



2. Flowering glumes hyaline, empty glumes membranaceous to 



coriaceous, the lowest the largest, its edges embracing the 

 others; axis of the inflorescence usually articulated (contin- 

 •uous in Imperata and Miscanthus) 3 



2. Flowering glumes membranaceous to coriaceous, usually firmer 



in texture than the empty glumes, axis of the inflorescence 

 continuous, not breaking up at maturity 4 



3. Spikelets either staminate or pistillate, each in a separate inflo- 



rescence on the same plant, or in distinct parts of the same 



inflorescence Tribe I. mayde.e. (See page 10. ) 



3. Spikelets either all hermaphrodite or hermaphrodite aud stam- 

 inate, regularly arranged and usually in pairs, one sessile the 

 other pedicellate in the same inflorescence (both pedicellate 

 in Tracliypogon) .. Tribe II. axdropogoxe.e. (See page 15.) 



