CHORISIS OR DEDTJPLICATION. 



251 



sessile compound leaf of two leaflets. In the related order Fuma- 

 riaceae,each phyton of 

 the androecium is tre- 

 bled in the same man- 

 ner. The circles of 

 the flower in that order 

 are in twos through- 

 out, or dimerous. 

 There is first, a pair 

 of small scale-like se- 

 pals ; alternate with 

 these a pair of petals 

 which, in Dicentra, 

 &c. (Fig. 294-296), 

 are saccate or spurred 

 below : alternate and 

 within these there is a 

 second pair of petals 

 (Fig. 297) : alternate 

 with these are two 

 clusters of three more 

 or less united stamens, 

 which plainly stand in the place of two single stamens. The ar- 

 rangement of parts is shown in the annexed diagram (Fig. 298) ; 

 where the lowest line indicates the subtending bract, and therefore 

 the anterior side of the blossom ; the two short lines in the same plane 

 represent the sepals ; the two next within, 

 the lateral and exterior petals ; those aU 

 ternate and within these, the inner circle 

 of petals ; and alternate with these are the 

 anthers of the two stamen-clusters. The 

 centre is occupied by a section of the pis- 

 til, which, as will hereafter be shown, con- 

 sists of two united. The three stamens 

 are lightly connected in Dicentra (Fig. 296) ; but in Corydalis and 



FIG. 294. Dicentra Cucullaria (Dutchman's-breeches) with its kind of bulb, a leaf, and a 

 scape in flower ; reduced in size 295. A flower of the natural size. 296. The same, with the 

 parts separated, except the sepals, one of which is seen at the base of the pistil. 297. The inner 

 pair of petals, with their tips coherent. 



FIG. 298. Diagram (cross-section) of the similar flower of Adlumia. 299. One of the sta- 

 mens increased into three by chorisis (the lower part of the common filament is cut away). 



