A more general record of growth is contained in thetype of bone laid down; because a specific bone type islinked to a particular rate of bone apposition, arelationship known as ‘‘Amprino’s rule’’ (Ricql"es et al.1991; Castanet et al.2000 ; Sander 2000; Padian et al.2001; Margerie et al.2002 ).Thi s relationship is difficultto quantify because of the limited number of tissue typeswhich are deposited within wide (but non-overlapping)rate brackets.The fastest-growing bone is fibro-lamellarbone without LAGs (found today in large mammals),intermediate rates are indicated by fibro-lamellar bonewith LAGs, and low rates are indicated by lamellarzonalbone (found today in most reptiles) (Ricql"es et al.1991; Castanet et al.2000 ; Margerie et al.2002 ).