Anukramaṇī
The Anukramanis (Sanskrit: अनुक्रमणी, Anukramaṇī) (also Anukramaṇikā) are the systematic indices of Vedic hymns recording poetic meter, content, and traditions of authorship.
Anukramanis of the Rigveda
Six Anukramanis of the Rigveda are ascribed to Shaunaka: Anuvakanukramani, Arshanukramani, Chandonukramani, Devatanukramani, Padanukramani and Suktanukramani. Except the Anuvakakramani, other Anukramanis survive only in quotations found in the writings of Shadgurashishya.
The most important Anukramani of the Rigveda is Katyayana's Sarvanukramani (ca. 2nd century BCE), recording the first word, the number of verses, name and family of poets (rshis), names of deities and metres for each of the 1,028 hymns of the Rigveda. The Vedarthadipika, written by Shadgurushishya (12th century) is a significant commentary of this work.
Mayrhofer (2003) discusses the personal names contained in the Rigveda Anukramani, counting 543 items. Academic opinion regarding the age and authenticity of the tradition of these names is not unanimous. Mayrhofer suggests that Hermann Oldenberg (1888) was essentially correct in assuming that