This is one of the topics-prepared by the writer for his projected work Relationship between Chinese Novel and Buddhism. Among a number of the novels and dramas published in the Sung and Yuan dynasties, there were many stories dealing with Vaisravana and Nata (毘沙門天王與哪吒). Feng Shen Yen I (封神演義) and The Pilgrimage to the West (西遊記) introduce numerous legendary characters. However, readers of these publications usually are ignorant of the characters' religious background while the reference in Buddhist classics is fragmentary and inconsistent. In this article the writer points out extensively their origin, heritage, development of creation, etc. The vital theme of the article falls on several stories with No Cha (哪吒) as a central figure (alias Nata who is familiar to Chinese novel readers). The origin of the legends is traced. The popular ones are that No Cha was born a flesh ball, that he had returned his flesh and bones to his parents, that he was transfigured from a lotus flower, and that he had irritated his father so much that he was later imprisoned under a pagoda. In addition the writer specifically recemmends that a, the Four Travels actually has a Ming dynasty edition, thus refuting an early assertion of Dr. Hu Shih and Professor Sun K'ai-ti; and b, with appropriate assumption, the appearance of Feng Shen Yen I must have been earlier than the time that The Pilgrimage to the West was written by Wu Ch'eng-en.