Abstract: The present paper deals with the karyotype analyses of Pinus kwangtungensis Chun ex Tsian and Pinus densata Mast. endemic to China. Both of the karyotypic formulas of the two species found to be K (2n) =24= 24m, which are reported for the first time. The karyotypes of the genus Pinus ( 93 species and varieties ) are all composed of metacentric or/ and submetacentric chromosomes and belonging to 1A type. Based on the comparative analysis of . karyotypic data, the author has found that Subgen. Pinus is more advanced than Subgen. Strobus, and that the genus Pinus is the most primary one in Pinaceae and quite dis-tant from the other genera, although it somewhat related to Cathaya and Picea. It is, there-fore, approprite to regard Pinus as a monotypic Subfamily Pinoideae as suggested by Pilger.

Key words: Department of Biology