The remarks made by Mr. Haddow in the GeologicalMagazine, Decade III. Vol. IV. p. 519, seem to demand a reply.

1.—He complains of the multiplication of generic or subgeneric names of Ammonites.

2.—He laments the confusion which appears to have arisen concerning what have hitherto been regarded as recognizable species.

3.—He suggests that the trinomial system would obviate the necessity of any of these changes and be at the same time an advantage.