Abstract
Three adult Hynobius nigrescens with malformed legs were found in a sample of 165 specimens collected at Iwamuro-Mura, Niigata Prefecture, on March 7, 1979. In the left hindleg of specimen No. 1 metatarsal 2' arose from the basal part of metatarsal 2 and digit II' grew to the position of the underdeveloped digitus IV. In the right hindleg of specimen No. 2, brachydactylia resulting from poor development of the phalanges was seen. Specimen No. 3 had a foreleg-like dwarfish leg on the abdomen. The osteology of these malformed legs is described, and causative factors of the malformation are discussed.
