The nine sons of the dragon is a traditional name for a set of mythological creatures whose imagery is used in certain types of decorations.
The concept was first mentioned by Lu Rong in the Ming Dynasty, although similar set of creatures (not necessarily nine) is recorded even earlier.
The oldest known attestation of the children of the dragon list is found in the Miscellaneous records from the bean garden (菽園雜記) by Lu Rong (1436–1494); however, he noted that the list enumerates mere synonyms of various antiques, not children of a dragon.
[1] Several Ming Dynasty texts list what were claimed as the Nine Offspring of the Dragon (Chinese: 龍生九子), and subsequently these feature prominently in popular Chinese stories and writings.
The word "dragon head" (螭首) may be applied to some of the mentioned structures.