Academy of Sciences in Paris. 357 



St. Hilaire presented a memoir on tlie flowers of the resedse, of which 

 the following is a summary: After recalling the observation mac 1 " 

 by M. de Mirbel on the want of consistency in vegetable organiz. 

 tion, and remarking that, in some genera, a particular class of organs 

 will occupy precisely the same place as is occupied by a totally dif- 

 ferent class in a neighbouring genus, he observes that the family of 

 the resedae offers a remarkable example of this species of transposi- 

 tions. After a general description of the flowers, he examines their 

 parts in detail, and remarks that the petals in the bud are at first 

 perfectly simple, singly trilobate, and composed only of a cellular 

 tissue, which is more fully organized at the summit than at the base. 

 He observes that they then become denticulated and laciniated ; and 

 perceiving the rudiments of a second petal appear at the base, he 

 arrives at the conclusions that each petal of the resedye is composed 

 of two opposed and soldered or connected petals ; or rather that the 

 corolla of the great part of the resedce is composed of two verticilli 

 immediately surrounding the pistil. It has been said by many 

 authors, that the centre of the flowers of the resedye contains a sup- 

 port, surmounted by a lateral discus, the stamina, and the ovary ; but 

 this is not the case. In the greater number of species, the support is 

 hollowed at the summit, and forms a kind of calix, the top of which 

 incloses the base of the ovary. The calix is formed of two verticilli, 

 closely attached one over the other. The exterior verticillus is com- 

 posed of nectarian scales, attached together, equal in number to those 

 of the petals, and alternating with them, while the interior verticillus 

 is formed of the fixed base of the stamina, really monadelphic. Some- 

 times the edges of all the nectarian scales are developed ; but in 

 general all but one become abortions ; and in every case the alterna- 

 tion is preserved. The reseda luteola is, however, apparently an ex- 

 ception to this rule, as the edge of the only scale which is developed 

 isjin {opposition to one of the petals. But as it is shown that the 

 petal is composed of two petals fastened together, the alternation, in 

 fact, still exists. From this observation, M. St. Hilaire concludes that, 

 in the flower which is the prototype of the resedse, the additions take 

 place in the upper, and the suppressions in the lower part. He then 

 proceeds to consider the staminal verticillus, first alone, and next in 

 its relations with the petals. He shows that the movements which take 

 place in the stamina of the reseda? do not result from the ordinary 

 physical laws, but from a vital force which escapes our means of 

 observation, and points out several analogous phenomena in other 

 plants, particularly the darilla rugosa, in which the great divi- 

 sions of the calyx close over the young pericarpium, allow it to ripen 

 like the seed in a pod, open to allow its escape at maturity, and then 

 close again. By an examination of the reseda alba, he proves that 

 the number 10 is the type of the staminal verticilli of the resedoe, and 

 that this number, which presents, by turns, alternations and oppositions, 

 is disguised in the different species by multiplications and unlinings 



