Dr. F. R. Cowper Reed, in a paper entitled “Notes on the Affinities of the Genera of the Cheiruridæ”, points out that Sphærocoryphe belongs to the Cheiruridæ, while Staurocephalus, which has at first sight some superficial likeness to it, belongs probably to the Enerinuridæ.

THE series of minute, adherent species of Brachiopoda brought together in the following discussion are usually assigned by American palæontologists to the genus Strophalosia, but recent writers have come to recognize the fact that, in America at least, the genus Strophalosia is a polyphyletic group. Dr. Stuart Weller, in his monograph on the Mississippian Brachiopoda (1914), all but recognizes the generic value of these minute shells when he points out the lack of harmony in the series of forms which he places in the genus Strophalosia.

THE following account is based on the six specimens recorded by Dr. W. D Lang in his paper on “The Ibex-zone at Charmouth, and its relation to the Zones near it” After mentioning the occurrence, in the top of the zone, of an apparently new Polymorphitid, Dr. Lang added the following footnote: “A striking form, 3 to 4 inches in diameter, with numerous, very thin costæ. Two specimens were found (not in place) in the winter, 1915–16, by Lieut. Dan Haggard, who presented them to the British Museum. The author found parts of three specimens in place in the Pyritic Marls in June, 1916. A sixth specimen, the best preserved of all, has been in the British Museum many years, and is labelled ‘Said to be from Lyme Regis’.”

1. A sample of modern Fenland silt containing 8·98 per cent of carbonate was found on minaralogical examination to include dolomite as well as aragonite in its mineral assemblage.

2. The dolomite is present in fresh angular crystal grains which suggest a secondary and recent origin of the mineral. It has possibly been deposited from sea-water which periodically covers the foreshore of the Fenland border of the Wash.

3. The general mineral composition of the silt resembles closely that of certain geologically recent deposits of Cambridgeshire, and points to the boulder-clay left by the North Sea glacier as the chief source of the material of which the silt is composed. The silt has mainly been deposited by sea-currents which carry southwards the eroded glacial deposits of the South Yorkshire and North Licoln-shire coasts.

4. An attempt is made to interpret the results of a chemical analysis of the silt in the light of its mineralogical composition, chiefly with regard to carbonate, potash, and phosphate. Muscovite, is found to be the main source of potash, and apatite of phosphate in the silt.

IT is a fact well known to geologists that the drifts laid down in the peripheral portions of the area affected by the Quaternary Glaciation differ markedly from those developed nearer in to the glacial centres. Beyond, perhaps, a vague suggestion that this may have been due to different climatic conditions during the successive stages of the retreat, no adequate or even partial explanation of the phenomenon has ever been brought forward. Pursuing a line of thought suggested by Dr. Matti Sauramo, in his paper on the glacial retreat in Southern Finland, it now seems possible to offer an explanation based merely on the simple assumption of a greater degree of cold during the maximum of glaciation than obtained during the later stages of the retreat.