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Specimens which in no respect revealed their andro-monoecioiis 

 character during the whole summer, which only late in summer 

 produced male flowers in the umbels of the third or fourth order 

 or sometimes entire male umbels, are found connected by interme- 

 diate forms with specimens which already in the very first umbels 

 contain male flowers. 



Concerning the part occupied by male flowers in the constitution 

 of the peripheral and central umbellules, it must be remarked in 

 the first place that with all Umbelliferae whose umbels reach a 

 certain size, the peripheral umbellules consist of a larger number of 

 flowers than those that occupy the middle part of the umbel. In 

 some species those central umbellules may be very poor in flowers ; 

 with Daucus Cnrota the central umbellules often even consist of 

 only one flower. 



When it was stated that the part occupied in the umbellules by 

 the male flowers becomes greater the more they are placed near 

 the centre of the umbel, this must be so understood that as the 

 umbellules become more distant from the periphery the number of 

 bisexual flowers decreases and does so much more rapidly than the 

 number of male flowers. Hence the inner umbellules are often 

 entirely male while the outer ones bear a number of bisexual 

 flowers. 



This rule is not without exception, however. Tliere are namely 

 Umbelliferae in the umbels of which the central umbellule occupies 

 the top of the principal axis of the umbel and may consequently 

 be distinguished as the top-urabellule. 



Such top-umbellules are especially found with Carum Carvi and 

 Oenanthe fistulosa and occasionally, although not so regularly, also 

 with Daucus Carota. For such a top-umbellule now the rule does 

 not hold that the part occupied by the male flowers is greater than 

 in the surrounding umbellules. Such an umbellule contains a greater 

 quantity of bisexual flowers. With Carum Carvi I often found no 

 male flowers in the top-umbellule when all others, as well the 

 peripheral as the more inwardly situated umbellules had some of 

 them. In other specimens the number of male flowers in this top- 

 urabellule was smaller than in the other. 



Of Oenanthe fistulosa the umbels of the second order are in this 

 country much larger than those of the first order; they consist of 

 five to eight umbellules and agree in their constitution almost entirely 

 with that, indicated by Schulz for the umbellules of the first order. 

 Here as a rule a top-umbellule can be very easily distinguished; it 

 contains only a few (7 to 9) male flowers, but is for the rest entirely 



