108 THE INFLORESCENCE. 



end after a little attention it will be found that the eye will intuitively, as it were, 

 recognise the leading forms. "We now proceed to consider the several parts of which a 

 flower is composed. 



Fig. 198. The Cyme. Fig. 199. The Umbel. 



The Bract is the outermost envelope, and closely resembles a foliaceous organ, and 

 bears the like relation to the flower that stipules do to the leaf. Its colour is more or 

 less green, and as it oftentimes bears much resemblance to a leaf, it is not always 

 readily distinguished from those organs. The rule adopted in making the diagnosis is, 

 that all organs, of whatever size, form, and colour, which intervene between the true 

 leaves below, and the flower above, must be bracts. This definition is too expansive to 

 render the determination of this question easy in every case, and therefore much 

 attention must be given by the botanist to each particular instance of difficulty. 

 Whenever the last leaf on the one hand, and the Calyx (to be mentioned presently) on 

 the other, can be clearly determined, then whatever intervenes must be of the nature of 

 bracts ; but whilst it is to be distinguished from leaves only by its lesser size and 

 higher position, and from the Calyx by its foliaceous character and lower position, there 

 must be great difficulty in determining its nature in many instances. In some plants it is 

 necessary to know the number of the divisions of the Calyx, and then to regard all 

 parts external to these, even if almost identical in colour and structure, as bracts. 



So long as they resemble leaves it is not needful to attach to them any more parti- 

 cular name than that of bracts ; but when they are sensibly modified, it is convenient 

 to give them other designations. Thus in grasses they supplant all other coverings of 

 the flower, and are known as Glumes (Fig. 200). 



The arrangement of the parts in the flower of the grass is so peculiar as to present 

 much difficulty to the botanist, and consequently various designations have been given to 

 the parts or organs. The three parts which constitute the coverings of flowers are bracts, 

 calyx, and corolla ; but, in this great class of plants, either they do not exist, or they are 

 incapable of separate definition. On reference to Fig. 200, it will be observed that 

 there are a series of scales or valves connected by their bases to the common stalk 

 on which they are supported, and having their apices free and oftentimes prolonged 

 into beards or bristles. The outer ones, b 1, are large and empty, and are suitably termed 

 Glumes or Gluma exterior. "Within these are a series of similar but smaller, scales^ attached 



