184 



PRINCIPLES OF PLANT-TERATOLOGY. 



opposite the carpels : a good case of congenital trans- 

 position resulting from the tendency to fuse.* 



In the wallflower (Gheiranthus Cheiri) all six 

 stamens, in some flowers, while retaining for the 

 most part their normal position, are changed into 

 carpels which are fused with the normal pistil to form 

 a single pistil of eight carpels. The pair of abnormal 

 carpels on each side in the median position are not, in 

 most flowers, united by their margins, and their 

 ventral surfaces are obliquely directed towards the 

 normal pistil, while their replum is excessively deve- 



Fig. 134. — Cheiranthus Cheiri (Wallflower). Transverse section of 

 stamens and pistil showing carpellody of the former and their 

 adnation to the latter. st l , stamens of outer whorl ; st 2 , stamens of 

 inner whorl; c, carpels. 



loped and fills all spaces between them and the pistil, 

 helping to cement the whole congeries of carpels 

 together. Each of the transverse abnormal carpels 

 has a replum extending between its margins (fig. 134). 

 In other flowers none of the abnormal carpels are 

 fused either with the pistil or themselves, and each 

 is open, exposing the ovules. In others again an 

 intermediate condition occurs. Usteri saw in herm- 

 aphrodite flowers of the papaw (Carica Papaya) that 

 the stamens became changed into carpels; when this 

 happened the normal ovary aborted. 



* See footnote on p. 183, 



