404 Observations on the Organogeny of the Flower. 



verticils in these vegetables have for type of arrangement the num- 

 ber 3 and its multiples, and not the distichous alternation of the 

 flabelliform organs, which should be their normal state. 



" In the Dicotyledons the cells also become vivified one after 

 another, to produce bivascular or double individuals, and natu- 

 rally have for their normal type opposite organs, that is, the 

 number 2 and its multiples. However, this group presents all 

 imaginable modifications in its verticils, among which the num- 

 ber 5 predominates. 



" It would be absurd, in my opinion, to imagine that,for instance, 

 in Monocotyledons the organs originated in threes or sixes ; or 

 in Dicotyledons in threes, fours or fives, &c, arranged in more or 

 less verticillated spirals : this is not the case. In Monocotyle- 

 dons the organs are constantly simple, originating always one 

 after another, becoming symmetrical in due time according to 

 their peculiar organic laws, to be developed more or less directly 

 together. In Dicotyledons the organs also originate separately, 

 are constantly double, and are symmetrical in a special manner 

 on account of this organic complexity. From the equality or in- 

 equality of force of the individuals which they compose, result all 

 the organic modifications which are observed in stems, flowers, 

 fruits, and in all parts which compose them ; modifications which 

 are commonly produced by deviation, mediate or immediate, 

 grafting, complete or partial abortion of some of the phytons or 

 their members. It will be seen that the mysteries of these abor- 

 tions, &c. can only be explained when organogeny shall have 

 unveiled the causes. We have not yet enough facts to generalize 

 in a truly scientific manner, and prudence counsels us to wait. 



( ' However, since the theory of the development of particular or- 

 gans, produced by special cells, is not yet entirely demonstrated 

 to the eyes of all savants ; since the organic modifications, internal 

 and external, which cells experience in becoming animated and 

 converted into distinct cellular systems or protophytes, always 

 grafted from their origin, by their base and more or less by their 

 sides, verticil by verticil, are yet far from being demonstrated or 

 even known ; we shall only here provisionally consider the floral 

 verticils as concentric cellular systems, distinct and variously tu- 

 berculated (mamelonnes) , continuous one with another, but being 

 formed or vivified one after another from the circumference to 

 the centre, by defect or excess of the individual vitality of each 

 verticil : this does not form one of our least arguments in favour 

 of the theory of merithals." 



These considerations, the whole responsibility of which the re- 

 porter (M. Gaudichaud) personally takes, seemed necessary here 

 as an introduction to the following report on M. Duchartre's 

 memoir. 



