The external morphological characters of the Ixeris chinesis complex were examined using numerical analyses in order to elucidate the morphological variations and reexamine the diagnostic characters previously suggested by Kitamura (1956). Many of the external morphological characters examined indicated an overlapping pattern common to di-, tri-, and tetraploids. However, some characters, including plant height, radical leaf length, internode length, inner-involucre length, involucre length, and pappus length were specific to only diploids or polyploids. Various characters were classified as common to both triploids and tetraploids including outer-involucre length & width, and inner-involucre width. The outer-involucre width and pappus number of tetraploids exhibited intermediate values between those of diploids and triploids. Using a canonical discriminant analysis with 38 characters, two canonical discriminant functions were obtained. The proportion of CAN1 was 0.7344, while that of CAN2 was 0.2656. The distinct classification of diploids and polyploids was straightforward using CAN1, whereas, the differentiation between triploids and tetraploids utilized CAN2. However, it was more difficult to find a single clear discontinous character among di-, tri-, and tetraploids when using a tukey multiple-comparison and canonical discriminant analysis. Most of their common diagnostic characters indicated an overlapped pattern. These results appear to support the subspecies classification scheme of these complexes, as suggested by Kitamura, i.e., Ixeris chinensis subsp. chinensis with yellow ligules indicate diploids, I. chinensis subsp. strigosa with white or purple ligule indicate
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