OP CENTRAL APUICA. 383 



the order Resedaceee is not included in the first or second 

 part of his 'Prodomus/ and I can find no observation 

 respecting it in these two volumes. It is probable, there- 

 fore, that he may intend to place it near Passiflorese, as sug- 

 gested by M. Tristan, or, which is more likely, that he has 

 adopted the hypothesis lately advanced, and ingeniously 

 supported, by Mr. Lindley, respecting its structure and 

 affinities.^ 



According to this hypothesis, in Reseda the calyx of 

 authors is an involucrum, its petals neutral fiowers, and pao 

 the disk or nectary becomes the calyx of a fertile floret in the 

 centre ; and, as a deduction from this view of its structure, 

 the genus has been placed near Euphorbiacese. 



The points in the structure of Reseda, which appear to 

 have led Mr. Lindley to this hypothesis, are the presence 

 and appearance of the hypogynous disk, the anomalous 

 structure of the petals, and the singular sestivation of the 

 flower ; but it is no slight confirmation of the correctness 

 of M. De Jussieu's opinion, that all these anomalies occur in 

 a greater or less degree in Capparidese, and have been found 

 united in no other family of plants. The remarkable aesti- 

 vation of Reseda equally exists in Crateva, and in more 

 than one subdivision of the genus Cleorae ; the hypogynous 

 disk is developed in as great a degree in several Capparidese ; 

 and an approximation to the same kind of irregularity in 

 the petals occurs in two sections of Cleome. 



The analogical argument alone then might, perhaps, be 

 regarded as conclusive against the hypothesis. But the 

 question, as far as relates to the petals, and consequently 

 to the supposed composition of the flower, may be decided 

 still more satisfactorily on other grounds. Both MM. 

 Tristan and Lindley regard the upper divided membrana- 

 ceous part of the petal as an appendage to the lower, which 

 is generally fleshy. On the other hand, I consider the 

 anomaly to consist in the thickening, dilatation, and inner 

 process of the lower portion, and that all these deviations 

 from ordinary structure are changes which take place after 



> Colkct. Boi, tab. 32. 



