This study was undertaken in order to evaluate and compare the effectiveness and fate of the nonautogenous scleral graft in relation to similar grafts of bone marrow and epithelium-free connective tissue grafts from the palate. One hundred round osseous defects 2 mm in diameter, were surgically created in the calveria of 25 rats. Three defects in each animal were filled with the various graft materials obtained from isogenic rats sacrificed at the time of preparation of the bony defects. The fourth defect was left empty as a control. The animals were sacrificed at varying periods of time up to 150 days. Histomorphologic evaluation of the graft sites demonstrated the following: (a) Scleral grafts had effected a functionally adequate repair, without apparent histopathologic changes. (b) Fresh bone marrow provided the greatest osteogenic activity when used as a graft implant. The sclera had an insignificant osteogenic activity when used as a graft implant. The sclera had an insignificant osteogenic potential. (c) Epithelium-free connective tissue was the least effective, both as an osteogenic or functionally adequate graft.