THE STRIKING clinical syndrome of blue scleras, brittle bones and otosclerosis has been accorded little attention by otologists in recent years. More reports have been made concerning the orthopedic and the ophthalmic than the otologic features. This may be explained by the fact that the deafness is a manifestation which usually occurs later, in the second or third decade of life, and therefore is less often included in the statistics. A possible clue to the causation of otosclerosis may be found through studies of this interesting and unique syndrome. Two cases studied at one of the Army hearing centers are reported in this article. The condition has been called osteosclerosis fragilis, fragilitas ossium and osteogenesis imperfecta. The cause is unknown, but there is a marked hereditary tendency toward the development of this condition, which all writers on the subject have emphasized. Henzschel,1 in 1831, and Gescheidt, in 1832, first described