ME. Q. BENTHAM ON GEAMINEiE. 23 



flowering glumes, leaving the intervening portion either attached 

 to the glume next above it, when it is usually described as a callus 

 proceeding from the glume, or to the glume next below it, when 

 it is often half concealed between the keels of the palea and taken 

 no notice of; or if it be a continuation of the rhachilla above the 

 last glume, it is often termed a neuter or abortive flower. The 

 cases where the flowering glume really detaches itself ultimately 

 from the inarticulate and persistent rhachOla are very few, chiefly 

 in several species of JEragrostis, where the glume and caryopsis 

 fall away, leaving the palea and floral axis persistent on the rha- 

 chilla. In some cases the apparently terminal fruiting glume 

 enclosing the palea and caryopsis falls away without any percep- 

 tible portion of the rhachilla above or below it ; but that arises 

 from the disarticulation taking place so close under it that the 

 fragment carried ofi' is only that minute portion actually em- 

 braced by the base of the glume. 



The homology of the glumes of Gramineffi, whether empty 

 or flowering, with those of Cyperacese may now be considered 

 as generally admitted ; and a total absence of perianth in the 

 former order might not be regarded as improbable when we have 

 traced in Cyperaceee its gradual reduction from the regular hexa- 

 merous perianth of Oreobolus to its absolute deficiency in Cyperus 

 and others. But we have in Graminese a new element on the 

 floral axis below the stamens and pistil or actual flower, in the 

 palea and lodicules, for which we cannot at once find any parallel 

 in other orders, and which have been very variously accounted 

 for. They have very recently been the subject of a very able 

 paper in Engler's ' Botanische Jahrbiieher' (i. p. 336) by Pro- 

 fessor Hackel of Vienna. He comes to the conclusion that the 

 palea and the pair of lodicules (when two only) are each of them 

 single, more or less bifid, organs, and that they and the third lodicule, 

 when present, must be regarded as two or three bracteoles inserted 

 alternately fore and aft on the floral axis below the flower. And 

 he has made out a good case in favour of his view, but perhaps 

 not an unanswerable one. The first objection that strikes one is 

 that the difficulty of finding any homologues in other orders is 

 by no means diminished. In other orders where bracteoles do 

 exist below the flower, they are usually lateral with reference to 

 the main axis, not fore and aft, never more than two, unless when 

 representing a continuation, as it were, of the sepals, and never 

 developed, to my knowledge, when the perianth is suppressed ; 



