(Chapter 21) Footnote 41:

Ancyroid or anchor-shaped. See, for example Galen De anat. adm. 1.275 and 4.471 (Singer 1956 pp. 29, 117), De ossibus 766 (Singer 1952 p. 773), De usu partium 4.131.8 (May 1968 p. 614)