CRUCIFERJE. 215 



12. The stamens are indefinite in one genus only, Megacarpcea. 

 There are in other cases six, tetradynamous ; very rarely are the two 

 lateral scarcely shorter than the four others. But sometimes some or 

 all of them disappear ; this occurs in Capsella, Lepidium, Nasturtium, 

 and Coronopus. Four out of the six stamens, the large ones, may even 

 disappear; or their filaments are reduced to tongues, sometimes 

 surmounted by a glandular dilatation. The staminal filaments are all 

 free ; or else the four longer are united in pairs to a variable height, 

 as in certain species of Fella, Sterigma, Anchonium, Boleum, Dontoste- 

 mon, Zerdana, Hexaptera, jEthionema, Euzomodendron, Leptaleum, 

 JSlyagrum, SpirorJignchus, &c. The base of the filament is sometimes 

 as it were articulated. It is here very contracted, but above may 

 expand into a circular rim or unilateral scale, or still higher up, it 

 becomes spreading, bowed, or angular, or is prolonged laterally into 

 a tooth or appendage, even a sort of wing in Lepidostemon. This 

 character is variable from species to species within a genus. The 

 anther varies in form and colour ; though usually introrse and 2-celled, 

 that of the large stamens is 1 -celled in Atelanthera. Sometimes the 

 form is a little different in the two sets of stamens. 



13. The ovary varies in form, nearly in the same way as the fruit, 

 and may bear the same prominences as we shall see thereon. It 

 often tapers into a more or less elongated style, sometimes laterally 

 dilated near the base (as in certain Matthiolas) into horns ; these 

 may occur lower on the g3 r na3ceum or fruit, as in Loncltopjliora, 

 Pgramidium, &c. The stigmatiferous apex is usually swollen, entire, 

 or very variably divided into connate, approximated, or divergent 

 lobes or horns. Pretty often there is no style and the stigma is 

 sessile on top of the ovary. This is normally formed of two lateral 

 carpellary leaves, and two alternating parietal placentas. 1 But one 

 of the latter may become in time quite abortive or be reduced to its 

 lower part, and bear no ovules ; and the other one may bear but 

 one or few ovules in only its upper or lower part. Thus the ovule 

 and seed appear suspended or erect, as the case may be. The ovules 

 are in form usually more or less campylotropous ; but some possess 

 a raphe of variable development, and cannot be distinguished from 

 ordinary anatropous ovules. 



1 We have seen that the cases of three or four especially in Tetrapoma (p. 181, note A, figs, 

 carpels and placentas must bs held anomalous, 210-213). 



