Abstract:Chromosome complements in cells of seedling root tips of Harrysmithia dissecta(a sole species belonging to the genus endemic to China),Pimpinella candolleana,Pimpinella flaccida,and Acronema paniculatum were surveyed.All four species had 18 chromosomes in each cell,and their karyotypic formulas were 2n=2x=18st,except for P.candolleana which was 2n=2sm+16st.Harrysmithia,Pimpinella,and Acronema not only have the same basic chromosome number,but also possess a similar karyotype.This suggests they are closely related taxa.It is reasonable,therefore,to include these genera in Carinae Drude with the treatment of Harrysmithia as an independent genus to be doubted.