296 



THE STRUCTURE OF FLOWERS. 



Bcpchia diosmoefolia ; * but as they grew on the interior of 

 the wall and not on an axile placenta, as is the normal con- 

 dition, in the Myrtacece, I expect that it was due to the 

 staminal vascular cords branching off and coming out of the 

 tissue within instead of at the summit of the hollow recepta- 

 cnlar tube, the carpels being more or less arrested. A not 

 t uncommon instance is to find the pistils of Willows with 

 open ovaries and bearing one or more anthers on the margins 

 (Pig. 78, a). I have met with a similar occurrence in 

 Banunculw auricomus (Fig. 78, 6). Pistils of other flowers 



Fig. 78 StameniferouB carpels of Willow 



(a) and Banunculus auriccmus (b). 



Fig. 19. — a, Petaliferous placeritas of Car' 

 damine pratensis; b, of Rhododtndron. 



way, 



have been known to bear anthers in a similar 

 Ghamcerops humilis, Trunus,^ etc. 



Pollen within ovules has been met with occasionally, as 

 in Passiflora and Rosa arvensis.X 



In some members of the Orucifera, as Gardamine pratensis 

 (Fig. 79, a), round pods are formed instead of the usually 



* Teratology, p. 184. Possibly the ovary wag entirely absent, and the 

 stamens would then be growing on the interior of a closed receptacnlar 

 tube, just as carpels grow upon the inside of the hip of a rose. 



t See Weber, Verhamdlung des Nat. Hist. Vereinea der Preuss Bhein- 

 v/nd Westph., 1860, p. 381. 



J Teratology, p. 185. 



