SAXIFRAGACEJE. 



403 



numerous anatropous ovules ; there are as many placentas as styles, 

 with which they alternate, as they do with the outer divisions of the 

 perianth when there are but three placentas. Tricerastes 1 often has 



Datisca cannabina. 



Fig. 490. 

 Male flower. 



Fig. 493. 



Tetrajnerous female 

 flower. 



Fig. 491. 

 Trimerous female flower (^). 



Fig. 489. 

 Male flowering branch. 



Fig. 492. 

 Long. sect, of female flower. 



hermaphrodite flowers, with a variable number of stamens between 

 the styles and the base of the superior perianth. The fruit which 

 has lost the perianth is superior, and opens only at the apex, into 

 three or more triangular valves, each continued above into one of 

 the branches of the style (fig. 494). The seeds (figs. 495, 496) are 

 very numerous, small and elongated. The outer coat is covered with 

 a prominent network ; and the fleshy subcylindrical embryo is 

 surrounded by a thin layer of albumen, or none at all. Only two 

 species of Datisca are known : one, with polygamous flowers inhabits 

 Mexico and the neighbouring regions ; 2 the other, 3 with dioecious 



1 Peesl, Eel. Easnk., ii. 88, t. 61. — Lindl, 

 Veg. Kingd., 316, ic.— Endl., Gen., n. 5017. — 

 A. DC, loc. cit., 411. 



2 D. glomerata. — Tricerastes glomerata 

 Pkesl, loc. cit.— Benth., PI. Eartweg., 334. 



a D. cannabina L., Spec., 1410. — Siuth., Ft. 

 GrcBC, t. 960. — CIeiseb., Spicil., 502. — Ledeb., 

 Fl. Ross., i. 238. — I). nepaleusis Don, Prodr. 

 Fl. Nepal, 202. 



1J D 2 



