In certain parts of the world, where the climate is very dry, we find examples of large salt lakes out of which no water ever flows towards the ocean. These lakes are fed by the rains and streams of the surrounding regions, but the evaporation from the surface is so great that it dries up the water as fast as it comes in, so that the lake remains stationary—the influx of water and the amount evaporated just balancing one another.

The species belonging to this Order, which are enumerated below and figured in the accompanying Plate, occur in the Lower Oolites without exception. The Oxfordian beds in Yorkshire have not been productive in fossils of this kind: the onlyknown species—Actœon retusus, Phil.—has already been described in the “Corallian Gasteropoda” (Geol. Mag. 1881, p. 127, Pl. IV. Fig. 7). The Tornatellidæ are the best represented, and especially Actœonina, but none are numerous, and really good specimens, suitable for accurate description, are rare indeed.

Syenite.—Much of the eastern coast of Essex County, Massachusetts, extending from Salem to a point beyond West Manchester, has been found by the writer to be occupied by a typical syenite of a reddish and greyish colour, which in its macroscopic characters appears to be identical with that from Planen'schen Grund, Saxony. The syenite in places contains much biotite, and also, near West Manchester, quartz grains (segregations ?). This syenite is often cut by dykes of a fine-grained greyish syenite, which holds the same relation to the syenite proper as the micro-granite dykes do to the granite of the region, and hence, for convenience of description, the rock of the syenite dykes may be styled micro-syenite

From time to time, during earthquake-shocks, magnetic compass-needles within the disturbed areas have been seen suddenly deflected from their position of rest, returning to it shortly, after one or more oscillations. This movement admits of two very different interpretations. Either it may be attributed to an intimate connexion between earthquakes and terrestrial magnetism, or it may be regarded asmerely a consequence of the shock of the earthquake. The object of this note is to point out a possible mechanical cause, and to guard, therefore, against a too hasty assumption of a magnetic origin for these disturbances