Note 648 — Chapter XVII · ON THE THEORY OF TRANSFORMATIONS, OR THE COMPARISON OF RELATED FORMS*
Reading edition
Cf. D’Orbigny, Alc., Cours élém. de Paléontologie, etc., I, pp. 144–148, 1849; see also Sharpe, Daniel, On Slaty Cleavage, Q.J.G.S. III, p. 74, 1847.