ON THE ASCLEPIADE^E.

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constant than the manner in which the pollen is attachedto the processes of the stigma in each species; and as con-siderable differences in this respect take place in variousspecies, I have with advantage employed these in the newgeneric divisions of the order which I have attempted toestablish, and to which I now proceed.

As I have everywhere mentioned the sources from whichmy knowledge both of genera and species is derived, itbecomes unnecessary particularly to notice here the extentof my obligations to the unrivalled Herbarium of SirJoseph Banks , who, with his accustomed liberality, haspermitted me to examine, and, where necessary, to dissectsuch specimens as seemed to have any peculiarity of struc-ture, and has thus enabled me to found my genera on amore satisfactory induction than I could have done in anyother part of the world.