6*00 Mr. T. Smith on certain Species of Cardans and Cnicus 



florets are smallest ; they project but little beyond the involu- 

 crum ; their laciniae are but slightly divaricate ; their imperfect 

 antherre do not rise above the apices of the laciniae of the corolla; 

 their filaments are never visible : in the hermaphrodite the sta- 

 mina project so much, that at the period of their full vigour the 

 filaments are seen above the tube of the corolla. These differences 

 are less obvious after the flowering is past; for, the stamina being- 

 retracted, the hermaphrodite is much more like the female : as to 

 numbers, the hermaphrodite is the most prevalent. 



In Serratula tinctoria, in which Mr. Brown first pointed out 

 the existence of female plants, 1 have not been able to satisfy 

 myself that males are to be met with ; for in the antheriferous 

 plants I have always found the ovaria impregnated. The seeds 

 of the female differ in being larger than those of the hermaphro- 

 dite. In this species plants occurred which showed a regular 

 gradation from the female to the hermaphrodite ; in one, the an- 

 thers? were much smaller, shorter, and more imperfect than they 

 most frequently are found in the female ; in another they were 

 as much larger, projecting, and embracing the style as in the 

 hermaphrodite, but containing only a few grains of abortive 

 pollen. 



The numbers of the female and hermaphrodite are nearly 

 equal. The stigma of the female is developed very soon after 

 the flower opens ; in the hermaphrodite, on the contrary, it does 

 not appear until the pollen of its own antherre is dispersed, the 

 style remaining undivided to the apex till this period ; the aid of 

 the antherae of some adjoining flower consequently becomes ne- 

 cessary for the purposes of impregnation. 



This is a striking example of a mode of impregnation which, 

 according to M. Cassini, prevails nearly throughout the whole 

 family of the Composite, and which renders the presence of two 

 flowers at the very least necessary to the impregnation of either ; 



constituting, 



