URTICIFLOM;. 



357 



Only 2 genera with 3 species (Asiatic), of which two are culti- 

 vated. Humulus lupulus (Hop, Figs. 347-349) is a twining, 

 perennial plant, twisting to the right, with opposite, palmilobed, 

 rough leaves, and large, interpetiolar stipules. The ? -flowers 

 are situated in closely-flowered, cone-like, compound inflores- 

 cences, with ultimately large, thin, imbricate floral-leaves (Fig. 

 348) which bear the yellow, glandular hairs, containing lupuliiu 



317. 348. 



FIG. 347-348. Humulus lupulus : 347, twining stem ; 348, branch with strobiles. 



This inflorescence is made up as follows : The most external floral-leaves are 

 situated in pairs, and are the persistent stipules of a leaf, the blade of which 

 has become suppressed, or in any case is rudimentary. Such a pair of stipules 

 supports 4 (2-6) flowers in a double uniparous cyme, whose central axis does 

 not develope into a flower. The bracts of these flowers (bracteoles of the 

 partial inflorescence) become, at maturity, very large, spathe-like, and, together 

 with the stipules, produce a cone-like appearance. 



Cannabis sativa (Hemp, Figs. 350-353) is an East Indian herb, 

 with palmilobed leaves, and differs from the Hop in being annual, 



