Mr. Woods on the Genera of European Gra.vses. 7 



frequently some small scales, which Limiœiis called nectaries, bnt which are 

 considered by some botanists as forming the true corolla of grasses, and by 

 Mr. Brown as vestiges of the interior series of a hexapetalous corolla. They 

 are the lodiculie of P. de Beauvois, and the glumeUiv of Richard. Squamula 

 is adopted by Knnth, and seems unobjectionable, as simply describing the 

 object, without determining- its use or involving- any theory of its origin. 



Mr. Brown* has proposed a division of the grasses into three unequal 

 groups, founded on the tendency of the genera to perfect the lower, the upper, 

 or only the central floret. In the first g-roup the number of florets is uncertain. 

 When there is only one, the outer valve of the corolla is at the inside of the 

 outer valve of the calyx. When there are two or more, they are either all 

 perfect, or the imperfection is in the upper florets. In the second group the 

 florets are either one or two ; the more perfect iluret being always next to the 

 inner valve of the calyx. The third group !i;is a perfect intermediate floret, 

 and one on each side either barren or still further reduced to a single valve. 

 The first contains the majority of the European grasses. The second. Sorghum, 

 Andropogon, Saecharum and Panician. The thii'd, Ilierocldoa, ^Inthoxantlinm, 

 and perhaps Phafaris. 



Where the object in view is an arrangement to facilitate the progress of the 

 student, we ought carefully to describe appearances. But in taking more scien- 

 tific views on the subject, we may be allowed to determine the nature of a part 

 by analogy, and pronounce that to be an abortive floret, which to unpractised 

 eyes appears to be only an additional glume. And perhaps in grasses the 

 most simple way is to consider every additional part without the palea as the 

 indication of an abortive floret. The tendency of certain plants towards a 

 particular structure, even when the structure is not developed, is very im- 

 portant, and was perhaps first distinctly implied in the observations of 

 Mr. Brown; but we must be careful in following this distinguished naturalist 

 not to push our theories too far, nor decide upon this tendency without the 

 support cither of a very close analogy, or of some indications in the plant 

 itself. AVhere there is no certain and definite character, different persons will 

 judge of relationship in very difterent manners. What seems clear and un- 

 questionable to one is very doubtful to another: and in arranging groups 



* This statement is taken from the Entrlish Flora. 



