The foraminifera here described were collected by C. Barrington Brown in the course of a survey as geological member of the Anglo-Italian Boundary Commission of Somaliland in 1929–30. We are indebted to him for the opportunity of investigating these specimens and for the use of his unpublished maps and field-reports.

The presence of small quantities of detrital (terrigenous) minerals in the Chalk has been recorded from such widely-separated areas as Northern France (1), the Isle of Wight (2), Antrim (3), Mull (4), and East Anglia (5), but the discoveries of boulders in that formation appear to be restricted to the south-east of England. These records may be due to the greater extent of the workings in the Chalk of that area, and hence the greater frequency with which these “foreigners” are uncovered, or to some definite geographical conditions prevailing in Cretaceous times. The information available seems to prove that Betchworth has yielded more boulders than all other areas added together. In 1897, W. P. B. Stebbing (6) described two granitic rocks from that area. The present paper deals with a small collection of nineteen boulders made by the late Gerard Weedon Butler, also from Betchworth. Since these notes were first drafted the writer has been informed that a collection of something like 70 boulders, mainly from Betchworth, has been added since 1912 to those that were already in the Museum of Practical Geology.

I venture to present before the Section a new interpretation of the Scottish Caledonide structure. This essay is based partly on the impressions that I got on a short visit to the Northern Highlands and on a most instructive excursion to Ballachulish under Mr. E. B. Bailey's inspiring guidance; partly on my own experience of the tectonics of Central European crystalline regions; but of course, above all, on the work of many Scottish geologists.

(1) The blocks of limestone in the Bowland Shales of School Share include a variety of rock-types of northern (Yoredale) facies and come from several beds near the Orionastraea Band of the Upper Viséan.

(2) They are a local accumulation at the local base of the Namurian (Upper Bowland Shales; zone of Eutnorphoceras pseudobilingue, E1 and rest, with evidence of some slight erosion, on one of the highest horizons of the Viséan (Lower Bowland Shales; zone of Goniatites spiralis, P2). Their horizon, therefore, is that of the mid-Carboniferous unconformity of Settle and elsewhere.

(3) They mark a comparatively small faunal hiatus (between the newsomi-meslerianum level immediately below and the C. malhamense level above).

(4) Their separation from the parent rocks and their assemblage are not due to tectonic causes. On the other hand, their great size points to some unusual form of transport.

(5) As they occur in a shale series near the Craven Faults they may legitimately be explained as the result of land-slips down s muddy slope from a limestone cliff, probably a fault-scarp raised by the mid-Carboniferous earth-movement.

(6) The circumstances recall those attending the Lower Palaeozoic conglomerates of Quebec. A recent explanation ascribes these to landslips caused by earthquakes from submarine fault-scarps. The School Share landslip may well have been caused by earthquakes, and the scarp from which the blocks were derived may have been essentially submarine.