Abstract: Bonan nationality was measured in 105 adult males and 103 adult females in August, 1988. Items of 44 direct measurements and 8 indirect measurements and 48 indices were investigated.
The measurements and indices of all individual were classified into different types according to the standards of Martin and Saller (1957).,Results can be summarized briefly as follows:
The average stature is 1634mm (male) or 1537 (female). In stature type, the frequencies of short. medium short, medium and tall are nearly equal both in male and in female. According to three different indices, most of the head types belong to mesocephaly, hypsicephaly and metriocephaly respectively both in male and in female. Most of the facial types belong to leptoprosopy and hyperleptoprosopy both in male and in female. Most of the nasal types belong to leptorrhiny both in male and in female. Most of the hand types belong to mesocheir both in male and in female.
The sexual difference presents more obviously in items of measurements than in items of indices.
Principal components analysis (PPCA) was made using anthropometric data of several nationalities or populations from northwest China. The characteristics used in PCA are head length, head preadth, minimum frontal breadth, facial breadth, bigonial breadth, physiognomic facial height, morphological facial height, nasal height, nasal breadth, mouth breadth (only in male) and stature. From the eigenvectors, we can conclude that PCI replesents size characters concerning the cephalo-facial breadth both in male and in female. PCII represents shape characters concerning the cephalo-facial breadth, length and height both in male and in female, and PCIII represents head length character in female.
Cluster analysis was made using the scores of PCI, PCII and PCIII instead of original variables. Accumulated contribution of PCl, PClI, and PCIlI reacher up to 96% in male and 93% in female. From the dendrogram of cluster analysis, Bonan is closes to Dongxiang, Hui, Han from Gansu, than to Mongol, Uygur, Tibetan and Han from Shaanxi Province.

Key words: Anthropometry; Bonan Nationality; Principal components analysis; Cluster analysis