[059]

PLATE 38. V. I. p. 347. Note.

Air chambers of Ammonites heterophyllus, filled with Lias, and shewing in a remarkable degree the effect of the undulating course of the edges of the transverse plates beneath the flat sides of the outer shell. [060]

A portion of the outer shell is preserved at c. and impressions of the fluted interior of the shell, which has fallen off, are visible at d. (Original.)