Akutagawa Ryunosuke(芥川龍之介 1892 1927) used a Japanese translation of The Spider-web, a Buddhist tale by Paul Carus (1852 1919), when he wrote Kumo-no-ito (蜘蛛の糸), his first work for children. Modern philological studies of Buddhism originated in Europe and excellent research results were produced there. Having taken advantage of them, Carus knew much about ancient Buddhist literature. According to the latest paper of Nagao Kayoko (長尾佳代子), his tale is faithful to the Buddhist tradition and coherent as a whole. On the other hand, Akutagawa, ignorant of Buddhist literature, missed Carus's points and failed to construct a coherent new story. In spite of its high reputation among critics, his Kumo-no-ito is a failure because of its inconsistency.