Notes on some Recent Foot-prints on Red Mud in Nova Scotia, collected by W. B. Webster of Kentville

Abstract

I beg to present to the Society some impressions of footsteps which Mr. Webster has sent me, at my request, from the mud-flats of Kentville in Nova Scotia. In my ‘Travels in North America,’ vol. i. p. 168. plate 7, I have given a plate and description of some of these foot-prints made by the sandpiper ( Tringa minuta ), which I saw daily running along the water's edge in the Bay of Fundy. The deposit there consists usually of red mud, with which the waters are charged by the undermining of cliffs of red sandstone and soft red marl. The tides rise very high, and when they are lowest, large areas recently overspread with red mud are laid dry, and are often baked in the sun for many days, so that the mud becomes consolidated and retains permanently the impressions of rain-drops, and the tracks of birds and animals which walk over it. Mr. Webster tells me, that the divisibility of the solid mud into layers arises from the deposit of each tide being separated by a layer of sand or loam thrown down when the tide first rushes along the bank. The sandy particles being the heaviest are first deposited, and then the thin layer of mud on which the birds walk when the tide recedes. On examining these specimens, I perceive that while some of the foot-prints standing out in relief on the under-sides of the slabs are casts of impressions made in a subjacent layer, and therefore do