Oospores and oogonia of Phytophthora citricola, in the same cultures on lima bean agar under moderate light and temperature conditions, germinated promptly and well without special treatment. On this medium many oospores apparently did not develop early dormancy. Most oospores germinated by one or a few straight germ tubes each bearing a sporangium which frequently proliferated, whereas most oogonia developed several often-branched tubes which infrequently terminated in sporangia.