158 TRANSACTIONS OF THE [Sess. lxxxi 



was also in cultivation, and flowered at Kew in 1907, but 

 it has not yet been described. 



The specimens of the series which I have had for 

 examination are far from complete. Of one only is there 

 certainly fruit. In only four species are the important 

 foliage-bud stage and the unfolding 3'oung leaves present. 

 I cannot hope in the circumstances to give an exhaustive 

 account of the species, but it may help the progress of 

 our knowledge if I state what I know of them, imperfect 

 though the statement must be. 



The plants are shrubs or small trees reaching a height 

 at maximum of some 9 meters, with usually not very 

 thick terminal branchlets — sometimes these are quite thin 

 {Rh. araiopliylhom). The shoots after the juvenile stage 

 appear to be glabrous in most species and are commonly 

 so described, but in Rh. pogonostylum an indumentum 

 covers the one-year old stems. Glabrescent would be the 

 more correct term. The leaves with short petioles from 

 1-5-2 cm. long (barely 1 cm. Rli. eritimum, 1 cm. only 

 Rh. araiophylliiin) are lanceolate, oblanceolate or oblong, 

 have a cartilaginous margin flat or slightly recurved and 

 always more or less undulate, sometimes notched some- 

 times only asperate. The leaf apex in the lanceolate and 

 oblanceolate forms tapers to a longish point, in the oblong 

 forms {Rh. agastum, Rh. eritiinum) is more or less suddenly 

 contracted into a beak-like extremity ; the midrib runs 

 out in all to the end of the leaf and enlarges into a small 

 horny hydathodal tubercle which, conspicuous in young 

 leaves and forming a distinct mucro, is in the old leaves 

 overgrown as it were by the lamina and covered by 

 it. The base of the leaf is cuneate or narrowly obtuse 

 in the lanceolate forms, more broadly obtuse in the 

 oblong, quite rounded in Rh. pogonostyhim. The upper 

 surface may be glaucous green {Rlt. adenosteTtionumi, Rh. 

 gymnanthwm, RJi. irroraium), more commonly an olive 

 green, sometimes showing a reddening along the course of 

 the midrib and primary veins {Rh. ceraceum) ; sometimes 

 in the older leaf becoming <juite a dark brown {Rh. 

 (j/lenoHte'monuin). The under surface is more variable, 

 passing froiri glaucous {Rh. eritimum) through straw- 

 coloured {R/i.. pogonostylum, Rh. spanotrichuvi) and fawn 



