Geology and Mineralogy considered with reference to Natural Theology/Plate 33
Plate 33. V. I. pp. 247, 248. Note.
Longitudinal Section of Nautilus Striatus, from the Lias at Whitby, in the collection of Mrs. Murchison. The interior of the Chambers is filled exclusively with calcareous spar, and that of the Siphuncle with Lias. (Original.)
Plate 34. V. I. p. 249. Note.
Drawing of the animal of the Nautilus Pompilius, prepared at my request by Mr. Owen, to show the manner in which the siphuncle terminates in the Pericardium. (Original.)
- The successive zones of this dark Spar show that the Lime composing it was introduced by slow and gradual infiltrations into the cavity of the air chambers. Hence it follows that no communication existed between the Siphuncle and these chambers, at the time when this Pipe was filled with the fluid mud, that has formed a cast of Lias within it. As the fractures across the Siphuncle in the 2d and 3d chambers are filled only with spar, of the same kind as that within these Chambers, these fractures could not have existed, when the Mud of the Lias formation entered the Siphuncle, without admitting it also into the chambers adjacent to them.