The Medals of Creation, Volumes 1 and 2 / First Lessons in Geology and the Study of Organic Remains

by Gideon Algernon Mantell

Lign. 153. Casts of chambers of Nautilus and Ammonite. (¹/₂ nat.)

Fig.	1.—	Cast in calcareous spar of a chamber of Nautilus. From the London Clay.
	2.—	Cast of a chamber of Ammonites excavatus. From the Coral Rag.

Lign. 154. Clymenia: ¹/₂ nat. Devonian.

Fig.	1.—	Clymenia Sedgwickii.
	2.—	Front view of the same.
	3.—	Vertical section of C. striata, showing the siphunculus on the inner edge of each septum.
	4.—	Suture of C. striata.

Clymenia ([Lign. 154], Ly. fig. 406).—This genus belongs to the Nautilidæ, and is peculiar to the Devonian deposits. It differs from the allied genera in the siphuncle being situated on the inner margin of the septa. The shell is discoidal, and the septa are very slightly lobed. At Elbersreuth, near Bareuth, in the N. E. of Bavaria, the Devonian strata abound in these shells; thirty-five species have been found, the greater number being peculiar to that locality.

In England they are chiefly found at South Petherwin, Cornwall, and in the Devonshire marbles. (See Phillip’s Pal. Foss. Devonshire.)

ORTHOCERAS.