UMBELLIFERrE 



205 



these, would otherwise naturally occur, is provided 

 against by the fact that the flowers are generally 

 protandrous, the stamens ripening before the pistil, and 

 the latter not being mature until the former have shed 

 their pollen, as, for instance, is shown in the following 

 enlarged figures of the Wild Chervil [ChcBrophyllum 

 sylvestre). Fig. 142 represents a floret in the earlier 

 (male) condition, showing three ripe anthers [a') and 

 two still immature (a), while the stigmas have not yet 

 made their appearance; in Fig. 143 the same flower is 



Fig. 142.— Wild Chervil in tlie first 



(male) state, 

 K, immature anther ; «', ripe anther ; 



Fig. 143. — Wild Cliervil in the second 



(female) state. 



nectary ; ov, ovary ; p, i)etal ; st, stigma. 



represented in a more advanced condition, the stamens 

 having fallen off', and the stigmas [st) being now 

 mature. 



In some cases flowers in both conditions may be 

 found in the same head or umbel ; in others, as, for 

 instance, in Myrrhis, the flowers of one head are all 

 first in the male condition, and subsequently in that 

 with mature stigmas, none of them arriving at the 

 second stage until they have all passed through the 

 first. 



It will be seen that in these florets the petals are 

 not symmetrical, the outer ones being considerably 

 larger than the others, and in many Umbellifers the 

 florets themselves, on the outer edge of the umbel, are 

 considerably larger than the inner ones. This dis- 

 tinction is carried still further in the Compositse, where 

 also the florets are so closely packed together that the 

 whole flower -head is commonly, though of course 

 incorrectly, spoken of as a flower. 



