I am greatly indebted to Mr. F. Spry for bringing to my knowledge some extremely interesting Upper Silurian fossils collected by him with great care and diligence from the tunnels excavated through the rocks underlying Melbourne during the progress of the new great drainage works for the city, carried out by the Metropolitan Board of Works. The age of the strata containing these fossils was originally determined by me for Selwyn's Geological Survey Maps of Victoria.

In the September number of the GEOLOGICAL MAGAZINE for 1898, Mr. J. S. Flett, B.Sc, describes, at p. 388, the occurrence of Allanite in the granite of Fell Hill, Cree Town, Kirkcudbrightshire, and in a biotite gneiss in Sunday, one of the Orkney Islands.

Many geologists have recognized that valleys, which have once been occupied by large glaciers, exhibit peculiarities which can only be ascribed to glacial erosion modify in g the earlier water-worn form of the land-surface. Indeed, anyone who allows ice-action to be locally a factor of importance in erosion, must expect that the resulting topographical forms will differ in some measure from those proper to water-erosion. Not only does ice,invirtue of its physical properties, obey different laws as regards pressure and flow, but, what is of equal importance, it fills the whole valley instead of following certain narrow channels. We may hope that, just as Gilbert and others have worked out the principles of watererosion, so the much more difficult problem of ice-erosion may some day be reduced to analysis. An attempt in this direction has been made by McGee in a paper on “Glacial Canons,” which, however, I cite here rather for its brief summary of the observed characteristics of glaciated valleys.

The marine Miocene shells from Egypt referred to in this paper form part of the collection of Egyptian fossils sent to the British Museum for determination by Captain H. G. Lyons, R.E., F.G.S., Director-General of the Geological Survey of Egypt.

Modern stratigraphical geologists, both those who study the Palæozoic and those who are occupied with the Neozoic rocks, are largely concerned with the establishment of zones;inother words, the zonal method of subdivision has been recognized as the best means of correlating the stratigraphical succession in one area with that of another. But when it comes to giving an exact definition of a zone there does not appear to be the same unanimity of opinion, and consequently it seems desirable that some wellconsidered definition of a zone should be put forward and discussed.

The subject of the average composition of collections of rocks has been dealt with in a paper published ten years ago by Mr. F. W. Clarke on “The Relative Abundance of the Chemical Elements.” The object of that paper was to arrive at an estimate of the mean chemical composition of the earth's crust, but incidentally the author shows a close correspondence between the mean compositions of groups of miscellaneous rocks from different regions. It appears from his figures that a moderate number of analyses—less than a hundred—if taken without any selection, is enough to give value to their mean. It may therefore be of interest to apply the method to our own country.

The first six volumes of Cretaceous Fossils and the first two volumes of Jurassic Fossils, described in this work, were issued without exact dates, and consequently have caused much confusion in nomenclature.