Description.—Shell trigonal, thick; umbones large, angulated and terminal, ending in acute points, which curve downwards, forwards, and a little outwards; the sides of the shell, triangular in form, slightly excavated and highly inclined to the areas, are bounded by prominent carinæ, an acute carina separating the side from the slightly concave triangular area in front, and a more rounded carina separating it from the slightly convex triangular area behind. The valves are marked with strongly defined and somewhat sinuous subimbricating lines of growth at wide and fairly regular intervals, between which may be discerned numerous fine lines of growth. Lunule small and deep. Cardinal tooth elongated, oblique and prominent in the right valve, small and triangular in the left.

A Comparison of adobe with the loess of China forms the concluding part of this paper; but as no analyses of the Chinese deposit are known to me, a few analyses of the loess of the Mississippi Valley are inserted, not with the assumption, however, that the deposits bearing the same name in these two regions are identical. A comparison of this table with the one showing the composition of adobe is instructive, as it indicates that these two yellow earths have a very similar composition. There are other respects in which they bear a close resemblance to each other; but as my acquaintance with the loess of the Mississippi Valley is limited, this comparison will not be carried further.

In an article published in the Geological Magazine for August, 1888, an outline was presented of some facts resulting from recent investigations on the glaciation of British Columbia and adjacent regions, bearing more particularly on the flow of ice in a northerly direction brought to light by explorations in the Yukon district, but touching also on the south-eastern extension of the great western glacier-mass of the continent, which I have proposed to name the Cordilleran glacier. Field-work carried out by me during the summer of 1888 has resulted in the accumulation of many new facts relating to the southern part of the area, which was at one time covered by the Cordilleran glacier, from which it would appear that it may ultimately be possible not only to trace the various stages in the recession of the main front of the great confluent glacier beneath which the interior or plateau region of British Columbia was buried, but even to follow the later stages of its decline as it became broken up into numerous local glaciers confined to the valleys of the several mountain ranges which limit the plateau.

In the present communication I call attention to a Reptilian vertebra which does not appear to have received the notice it deserves, and also give a preliminary diagnosis of certain forms which I hope to describe more fully later on.

In the winter of 1886–7 a boring was made at Bletchley Junction for the London and North-Western Railway Company, and acquired importance from the report that, after passing through the Oxford Clay, it had entered a mass of granitic rock. Probably many readers of this Magazine wondered why no detailed account of the boring was published after this announcement; but the reason was, that when inquiries came to be made, some uncertainty was found to exist as to the position and mode of occurrence of the granitic rock. My attention was recently called to the boring by learning that the water obtained from it was salt. I then obtained all the information I could with regard to the rocks passed through, and think the results are of sufficient importance for publication.

Among the local Museums of recent foundation, it would be difficult to find one of more scientific interest and importance than that of the Malton Field Naturalists' and Scientific Society. The commencement of the collection, indeed, was made so lately, that it might naturally be expected to have attained little beyond the nucleus-stage; but as an exponent of local Natural History it already rivals many of the older Museums, and the object of the present notice is briefly to call the attention of palæontologists to the material it affords for all interested in the investigation of Jurassic and Cretaceous fossils.