OF CENTRAL AFRICA. 283 



the order Rcscdaccnc is not included in tlie first or second 

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

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

 fore, that he may intend to i)lace it near Passiflorcoc, as sug- 

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

 adopted the hypothesis lately advanced, and ingeniously 

 snpported, by Mr. Lindley, respecting its structure and 

 affinities.-^ 



According to this hypothesis, in Reseda the calyx of 

 authors is an involucrum, its petals neutral floAvers, and [220 

 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 Euphorbiacca?. 



The points in the structure of llescda, which appear to 

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

 and appearance of the hypogynous disk, the anomalous 

 structure of the petals, and the singular aestivation of the 

 flower; but it is no shght confirmation of the correctness 

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

 a greater or less degree in Capparidea), and have been found 

 united in no other family of plants. The remarkable a3sti- 

 vation of Reseda equally exists in Crateva, and in more 

 than one subdivision of the genus Cleome ; the hypogynous 

 disk is developed in as great a degree in several Capparidea) ; 

 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. ]]ut 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 



' Callecf. But. tab. 22. 



