Ruchin A. B. RussiaPushta TownMordovian State Nature Reserve named after P. G. Smidovich, Pushta Town, Temnikov Dist., Republic Mordovia 431230, Russiasasha_ruchin@rambler.ru Author's articles ON THE NUTRITION OF SOME SEMI-AQUATIC AMPHIBIAN SPECIES (AMPHIBIA: ANURA) IN THE NORTHWESTERN UPPER OKA REGION