68o 



SCIENTIFIC RECREATIONS. 



termed rachis, and which bears numerous leaflets called bracteoles or bractlets, 

 from whose axils arise the pedicellate or sessile flowers. The lower bracts 

 often produce no flower-buds in their axils, and form instead a whorl sur- 



Fig. 778. Raceme. 



Fig. 779. Panicle. 



Fig. 780. Corymb. 



rounding the heads of flowers on the primary axis, and which is called 

 involucre (as in the sun-flower, for instance). 



The different varieties of axillary inflorescence are determined princi- 

 pally by the elongation or depression of the axis, the presence or absence of 

 stalks to the flowers, and the form and nature of the bracts. We distin- 

 guish 



i. (i) lias spike (fig. 777). In this form of inflorescence, sessile or 



Fig. 781. Umbel. Fig. 782. Capitulum or ball. 



short-stalked flowers are arranged along the rachis in the axils of the 

 bracts ; the spike is said to be compound when small spikes or spikelets 

 arise again from the bracts of the secondary axis. (2) The catkin or 



