( 8J0 ) 



very general as well on sandy soil (at the edge of the dnnes) as on 

 fertile clajgronnds. Both plants can be best judged by the constitntion 

 of the nmbels of the second order. 



Of Anthriscus silvestris the average constitution is : 



on sandy soil on clay ground 

 of the six outer umbcllules 4-5«+ii-J3r!' 7.io"^+3-4d' 



of the seven inner umbellules 2-4^+ 8-1 Icf 6-7?-|-4-7cr 



And of Chaerophyllum teimthim : 



of the outer umbellnles JSg + JOd'+l^ 20^+70"+!? 



while the 2 or 3 innermost umbellnles of the plants on sandy soil 

 are entirely male. 



So the results are in perfect agreement with my observations on 

 the intluence of the fertility of the soil on the appearance of clias- 

 mogamic flowers with Ruellia tuherosa at Batavia and with those 

 of GoEBEL on the chasmogannc flowers with Jmpittienfi noli tangere 

 in places of different fertility near Ainbach '). 



From what has been communicated here it appears that the andro- 

 monoecious Umbelliferae in the natural state have the character of 

 ever-sporting varieties in wdiich the racial character, the bisexual 

 flower, is in a semi-latent condition. 



By assuming this it becomes clear why the anomaly shows itself 

 least in the terminal umbel, why, after it has once appeared, it 

 increases in number in the mnbels of higher order, why in each 

 umbel the number of hermaphrodite flowers decreases from the 

 jieriphery to the centre, why in each nmbellule the bisexual flowers 

 are placed at the circumference and the male ones at the centre and 

 why with those species in which the umbels have a top-nmbellule, 

 this latter often has again relatively more bisexual flowers than the 

 suri'ounding umbellules and finally why, where in the umbellules 

 a top-flower is found, this is as a rule bisexual and holds out longest 

 when the umbellules grow more and more male, so that it often 

 still occurs in such umbellules where the bisexual marginal flowers 

 have already had to give way to the male ones. 



Although I am of opinion that many things plead for my conception, 

 yet I am perfectly aware that certainty about the true nature of the 

 race, about the influence of fluctuating variability on the numerical 

 relations between bisexual and male flowers, about the question 

 whether perhaps locally different varieties or ever-sporting varieties 



1) GoEBEL. Die kleistogamen Bliiten und die Anpassungslheoriëu, Biol. CeiitralbL 

 Bd. XXIV. No. 24, p. 770. 



