212 



ORGANOGRAPHT. 



A-eloped at each ramification is indicated by a dotted line. 

 In consequence of this one-sided, (or as it is called secund) 

 manner, in whicli the secondary branches are produced, the 

 direction of the inflorescence is constantly drawn to one side at 

 the formation of each axillary branch, and that in proportion 

 to the size of the angle formed by it with the branch from 

 which it springs, and thus when the angle is large, and 

 many flowers are produced in succession, the upper extremity 

 becomes completely coiled up in a circinate manner. In a 

 plant Avith an alternate arrangement of its leaves or bracts, 

 the hehcoid cyme, arises from the primary axis {Jig. 418, 1) 



being terminated by a 

 Fig. 418. flower, and giving off 



below it from the upper- 

 ? ^ most bract or leaf a 



secondary axis 2, which 

 also terminates in a 

 flower, and gives otf in 

 like manner, from the 

 same side as the former 

 a third axis 3, and so 

 on, as seen by the figures. 

 The place of the bracts 

 is indicated by the dotted 

 lines. Hence, such a 

 cyme consists of a series 

 of single-flowered axes 

 (unifloral) arranged in 

 the form of a raceme, to 

 which kind of inflores- 

 cence it is by some bo- 

 tanists considered to 

 belong. When the bracts arc developed, however, there ought to 

 be no difficulty in distinguishing it, as in the ordinary raceme the 

 flowers always arise from the axil of the bracts, Avhereas in the 

 hehcoid cyme they are placed opposite to the bracts, or at all 

 events out of the axil {fig. 418). In those cases, however, where 

 the bracts are abortive, as in most of the Borage tribe, its dis- 

 crimination from the true raceme is often difficult or even im- 

 possible, and its nature can only be ascertained by comparison 

 with allied plants. 



c. The Fascicle or Contracted Cyme — This name is applied to 

 a cyme which is rather crowded with flowers placed on short 

 j)edicels of nearly equal length, as in the Sweet-William and 

 some other plants of the Pink tribe to which it belongs. 



d. Tlie Glomerule. — This is a cyme which consists of a immber of 

 sessile flowers, or those where the pedicels are very short, collected 

 into a rounded head, or short spike. It is seen in species of Nettle 



Fig. 418. Diagram to illustrate the formation 

 of a Bcorpioid cj'me in a plant with alternate 

 bracts. The figures represent the respective 

 axes, and the dotted lines the position of the 

 bracts. 



