Notes on Indian Botany. 177 



Every flower in my specimen has so suffered from attacks of in- 

 sects, that I could only find one in a fit state for dissection, and from 

 it we learn, that this species has a 5-lobed corolla, 15 stamens, and a 

 10- celled ovary. Here is a marked departure from all the other 

 sections of the genus : hence, if further acquaintance with the species 

 establish the correctness of these numbers, this must form either the 

 type of a new section or of a genus." 



CONVOLVULACE^E. 



RlVEA ARGYREIA AND LETTSOMIA. 



M. Choisy, in his memoir on Indian Convolvulaceae, in tak- 

 ing up Loureiro's genus Argyreia, has changed its character 

 so essentially, that every one of Loureiro's genuine species 

 must now be excluded. I say genuine, because if Choisy 

 is correct in referring Argyreia /estiva, Wall, to A. acuta, 

 Lour., which I doubt, then that is not a true species of his 

 genus, which, as defined by himself, has a 4-celled ovary, 

 while A. f estiva has it ^-celled. 



Loureiro's character of the fruit of Argyreia is " bacca 

 subrotunda exsucca 4<-locularis" Choisy's " ovarium 2-locu- 

 lare 4-spermum." If the berries in Loureiro's plants have four 

 cells, it is obvious the ovary must have had at least an equal 

 number : hence, in assigning a 2-celled ovary to Argyreia, 

 Choisy has altogether suppressed the original genus, and set 

 up a most distinct one in its place, while at the same he has 

 added to the confusion by placing in his new genus, numer- 

 ous species with 4-celled ovaries and fruit. In fact, nearly 

 the whole genus, as it now stands in DeCandolle's Prodro- 

 mus, will, I apprehend, be found not to come within his 

 generic character. 



It is a curious fact, that Roxburgh fell into a similar error 

 in regard to his genus Lettsomia, which according to his 

 definition has 2-celled ovaries, while nearly all his species 

 have them 4-celled. When both he and Loureiro wrote, the 

 same importance was not attached to that point of structure 



2 A 



