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hermaphrodite, wliilc the sidc-ninbolhilcs are generall}' exclusively 

 male. 



Wi(h Daiicus Carota, where (lie uinlteliulc as was remarked 

 abo\e, often oonsist.s of no more than one flower, this latter is very 

 often hermaphrodite, also when the surrounding umbellules consist 

 entirely of male tlowers. 



It must still be remai'ked for the andro-monoecious Umbelliferae 

 that both sorts of flowers as a rule occupy a fixed place in the 

 umbellule. 



In by far the most Umbelliferae the bisexual tlowers are found 

 near the edge and the male ones in the middle. 



Only a few make an exception to this rule; with Oeiianthe jistulosa 

 and Sanicula europaea the opposite is found and with Astrantia the 

 bisexual flowers as a rule occupy a definite zone between the peri- 

 pheral and central male flowers. Advancing from the circumference 

 to the centre we find there first one or two whorls of male flowers, 

 then a whorl of bisexual ones and finally at the centre male flo- 

 wers again. 



But although it may be the rule for all other Umbelliferae that 

 in all the umbellnles, containing the two forms of flowers, the her- 

 maphrodite ones are placed at the edge and the male ones in the 

 middle, an excejition must be made for those Umbelliferae which 

 in the middle of the umbellules develop a top-flower, for this latter 

 is as a rule bisexual. 



Such top-flowers are e.g. regularly found with Chaerophyllum and 

 with Meum; in each umbellule of Chaewphi/IIum temu/inn and Afeum 

 athamanticum bisexual marginal flowers and a bisexual top-flower 

 are found and for the rest male flowers. 



Also with Aegopodium Podograria, Canim Carvi and Daucus 

 Carota bisexual top-flowers are fonnd in the umbellules, but in these 

 species this top-flower is not always found in all umbellides. 



No extensive argument will be needed to understand that the two 

 forms of flowers, found in the same individual of the plants men- 

 tioned, may be considered, like the two flowers of a cleistogamic 

 plant, as two antagonistic characters which mutuall}' exclude each 

 other and that consequently these plants may be compared with 

 ever-sporting varieties, originated by mutation, the existence of which 

 was shown by de Vries. 



Every andro-monoecious Umbellifei'a of which we compare a 

 number of individuals among themselves, affords an opportunity for 

 noticing that the two antagonistic characters evidently fight for 



