Note 450 — Chapter XIII
Reading edition
Hist. Crust. Foss. pl. xi. fig. 6.
[451] See Mr. Prestwich’s Memoir on the Geology of Coalbrook Dale, Trans. Geol. Soc. second series, vol. v. part 3.
[452] Trans. Geol. Soc. second series, vol. v. pl. xli. figs. 1-4.