Saw Salter's Spirifer specimens; a very good proof of indefinite modifiability.
Beginning to think gap between Cambrian and Lower Silurian enormous.
Édouard Lartet to give paper before Geological Society ["On coexistence of man with certain extinct quadrupeds", Q. J. Geol. Soc. Lond. 16 (1859–60): 471–5].
53, Harley S
May 7. 1860
My dear Darwin
I saw Salters spirifers, a very good proof of the fructifying nature of your indefinite
modifiability principle. I also asked him if he did not think
that Barrandes ``primordial'' (the Cambrian of Manual 5
Suppose the gap as I begin to suspect to be as great as between Cretaceous & Eocene what a grand discovery the Cambrian type is—
On Wednesday May 16
- f1 2787.f1See letter to Charles Lyell, 4 May .
- f2 2787.f2Joachim Barrande believed that the lower Silurian formations around Prague constituted a new system, which he named the `Primordial'. Comparable rocks in Britain were the subject of heated debate between Adam Sedgwick and Roderick Impey Murchison. Sedgwick insisted, like Barrande, that the formations were sufficiently distinct to merit a separate name (the `Cambrian'); Murchison, on the other hand, maintained that they were merely part of the lower Silurian. In his Manual of geology (C. Lyell 1855, pp. 452--5), Lyell had given his support to Sedgwick's view. For a study of the debate, see Secord 1986.
- f3 2787.f3Huronian and Laurentian formations, which were being actively studied by members of the Geological Survey of Canada at the time, were later identified as pre-Cambrian. See Zaslow 1975.
- f4 2787.f4Casiano de Prado began a geological survey of Spain in 1848.
- f5 2787.f5´Edouard Amant Isidore Hippolyte Lartet's excavations of flint-bearing sites helped to establish the contemporaneity of man and extinct animals (DSB). His paper `On the coexistence of man with certain extinct quadrupeds' (Lartet 1860) was read at a meeting of the Geological Society on 16 May 1860. Leonard Horner, president of the society, contributed remarks that were printed with the paper.
- f6 2787.f6The number of CD's portfolio of notes on palaeontology and extinction.