The cause of changes in Climate during past Geological periods having lately become, and being likely to continue, a prominent topic of interest, I have attempted here to bring together the more prominent features in the controversy, under the idea that to many readers, who have not either the time or the inclination to more closely examine the subject, this may be acceptable. In so doing I have, with one partial exception, confined myself to discussing the difficulties which beset all the various theories offered as a solution, rather than attempted the advocacy of any one of those theories in particular.

Amongst the undescribed sponges from the Cambridge “Coprolite” bed, which have come under my notice, is the beautiful hexactinellid that forms the subject of this communication.

Coast Ice of Newfoundland.—Icebergs have an advantage over coast-ice in their imposing appearance, which has perhaps been in part instrumental in raising them to the high position which they now occupy as workers of Geological changes. Many Manuals of Geology, and many diagrams drawn to illustrate the same science, have oft-times portrayed a well-known flat-topped berg, carrying a rock, in the Antarctic regions; but neither books nor lecture-diagrams, taken collectively, give any adequate idea of coast-ice as a similar agent. From what I have seen of coast-ice and of its effects. I feel persuaded that it is an agent of at least as great, if not of greater universality than either glaciers or icebergs, and taken as a whole perhaps also as an agent of equal power. Of the various forms of sea-ice known as “berg-ice,” “floe-ice,” “pack-ice,” and the like, the portion I would more particularly draw attention to is that variety which forms a narrow belt along the shore, known in Greenland as the “Ice-Foot.”

The recent discovery of fossil fishes in the Carboniferous beds of North Devon appears of sufficient importance to require that the facts connected with it should be placed on record.