A Classification of Codonopsis

In the 1931 monograph "Some Notes on the Genus Codonopsis" J.A.Nannfeldt begins by describing a classification based on the earlier (1926) work by J.Anthony but with several enhancements mostly around the area of the "ovata" subgroup. I would not agree entirely with this classification, especially regarding the dicentifolia and kawakamii placements, although Nannfeldt appears not to be convinced himself on these points, also this is by no means a complete survey of the genus. However, I have found it helpful and for this reason I thought it worthwhile producing the diagrammatic summary of his text below.