GAPPABIBAGEM. 



145 



bud. 1 Above this is a corolla of four alternating free petals, twisted 

 or imbricated in the bud. The androceum consists either of four 

 stamens alternating with these, or, more frequently, of six stamens — 

 two lateral, two anterior, and two posterior. 2 Each has a free filament, 3 



Clet. 



nne spinosa. 



Fig. VJl. 



Flower. 



Fig. His. 

 Diagram. 



Fig. 1(50. 

 Long. sect, of flower (£). 



and an introrse two-celled anther of longitudinal dehiscence. 4 Between 

 the perianth and androceum, the surface of the receptacle is swollen 

 into a glandular disk, sometimes complete, sometimes only between 

 the feet of the petals. 5 The free superior ovary is sessile or stipitate ; 

 it is narrow and elongated, surmounted by a short style ending in a 

 more or less flattened dilatation covered with stigmatic papillae. In 

 the single cell of the ovary are two parietal placentas, each bearing 

 an indefinite number of subcampylotropous ovules in two or more 



Gen., n. 4985.— Payer, Orga.wg., 201, t. 42; 

 Fam. Nat., 134.— B. H., Gen., 105, 068, n. 2. — 

 Micavibe Marcgr., ex Adans., Fam. des PL, 

 ii. 407. — Sinapistrum T., Inst., 231, t. 116. — 

 Mojnch, Meth., 250. 



1 They are equal or slightly unequal. They 

 often separate from one another for a variable 

 distance at their bases before their apices have 

 parted. Still more frequently the petals fall to 

 the posterior side of the flower, while the stamens 

 protrude partially through the cleft of the peri- 

 anth on the other side. 



2 They are usually inserted at some distance 

 VOL. III. 



from the corolla, and between the two verticils 

 the receptacle is somewhat dilated, and spherical 

 or conical. This interval of; en increases with age. 



3 Either the filaments of all the stamens are 

 equal, or else those of the lateral ones are a little 

 shorter, as in Cruciferce. They are sometimes 

 dilated towards the apex. 



4 The pollen grains are ellipsoidal, with three 

 longitudinal folds. Moistened, they become 

 spherical with three glabrous bands (H. Mohl, 

 in Ann. Sc. Nat , ser. 2, iii. 327). 



5 Sometimes a large gland behind is separate 

 and prominent, into a horn or spur. 



L 



