In spite of the fact that dry beans (Phaseolus vulgaris) are one of the main sources of protein in the State of São Paulo, Brazil, they are considered a secondary crop and grown only in small patches or intercropped with coffee, sugar cane, or corn. The development of high yielding strains resistant to the most prevailing diseases, has been considered of prime importance, in order to increase the annual harvest, which is of the order of 150,000 metric tons, grown in an area of approximately 360,000 ha. A project was initiated in 1930 in the Genetics Department of the Instituto Agronômico, Campinos, in order to find out which of the numerous cultivated commercial varieties were most suitable. Several strains were developed from these varieties, resistant to the physiological races of the rust occurring in Campinas, which have been tested in several ecological regions, in order to evaluate their yielding performance. From these varietal and strain trials, undertaken in the period 1948-1956, it was concluded that the beans belonging to the "Mulatinho" and "Chumbinho" types were the most promising ones. These and the new strains here developed or imported from other bean research centers, were object of a new series of eight trials, which is being discussed in this present paper. These strains were assembled in eight groups according mainly to their growth habits and seed characteristics. The seed weight wos compared with the whole plant weight at the harvesting time, for the eight groups of varieties. The obtained indexes showed to be variable according to the groups of varieties and so can be useful in their identification. They also indicate the yielding capacity of the analysed groups. An analysis of these groups of varieties indicated that the highest yields were observed among the varieties of the "Prêto" group, with black seed coat and Rosinha, with light rose seed color. The I-43-C variety received from Venezuela also showed to be of value far our ecological condition. According to the results here presented special attention should be given to the varieties of the "Prêto" and "Rosinha" groups for further development of better dry bean strains.