On June 25th, 1950, a fragment of humerus was discovered by Mr. H. YOSHIZAWA and Mr. T. KANAZAWA in No. 1 cave of No. 10 quarry of YOSHIZAWA Limestone Mining Industry Co. Ltd. in Ogano, Kuzu-machi, Aso-gun, Tochigi Prefecture. This specimen which lacks its trochlea and capitulum is a right humerus of a non-adult. His shaft is slender, but the opening in the lower part is equally developed as an adult's, and his anconeal fossa is located rather on the external side. Consequently, it is probable that this specimen is a human bone although it cannot be said to be normal. And further, a fragment of the shaft of a woman's left humerus was found in the same cave on Aug. 21st, 1950. The specimen is also young and resembles the shaft of chimpanzee though it has been defaced by running water. However, the osteological characters show that it is also a human bone. It may safely be said that these two specimens described above are the fragments of bones of the original human beings whò were akin to the ape.The deposit of this cave presumably was drifted by flood into this cave with the human bones together with other natural remains, it is guessed. It was piled up against a heap of loam, because this cave is covered all over with loam which is found widely in the Kanto area. I am assured that the geological age of this layer is the Middle Pleistocene or Lower Pleistocene from the items of other fossils which have been found with these human bones. The following fossils have been found in this cave:Mammals: Mogera wogura wogura, Urotrichus talpoides hondonis, Chimarrogale sp., Apodemus sylvaticus speciosus, Canis lupus lupus, Ursus sp., Megaceros sp., Cervus praenipponicus, Palacoloxodon nanmanni, Macaca fuscata.Birds: Corvus sp., Fringilidaea gen. et sp. indet.Amphibia: Bufo sp.Reptilia: Clemmys sp., Natrix sp.Moreover, a piece of a human left femur was found in this cave on July 25th, 1950. I should like to name it Homo? Tokunagai as a type-specimen. I am going to report on it in another article. It is my belief that the two fragments above described belong to the same species.