References:--"Air-breathers of the Coal Period." Montreal, 1886. Papers on Reptiles, etc., in South Joggins Coal Field, _Journal of Geological Society of London_, vols. ix. x. xi. xvi. Remains of Animals in Erect Trees in the Coal Formation of Nova Scotia, _Trans. Royal Society_, 1881. "Acadian Geology," fourth edition, 1891. Revision of Land Snails of the Palæozoic Era, _Am. Journal of Science_, vol. xx., 1880. Supplementary Report to Royal Society of London, Proceedings, 1892. Notice of additional Reptilian Remains, _Geological Magazine of London_, 1891. _MARKINGS, FOOTPRINTS AND FUCOIDS._ DEDICATED TO THE MEMORY OF THE LATE DR. J. J. BIGSBY, F.R.S., OF LONDON, The painstaking and accurate Author of the Thesaurus Siluricus and Devonico-Carboniferous, a warm and kind Friend and Christian Gentleman and one of the Pioneers of Canadian Geology. Reminiscences of Lyell's Work--Tidal Flats of the Bay of Fundy--Rill Marks and Shrinkage Cracks--Worm Trails and Burrows--The Paces of Limulus--Fucoids Versus Trails--Footprints of Vertebrates [Illustration: Track of Limulus.--Modern, Orchard Beach. Showing its resemblance to the _Protichnites_ of the Cambrian. (Page 320.)] CHAPTER XI. _MARKINGS, FOOTPRINTS AND FUCOIDS._ I believe my attention was first directed to the markings made by animals on the surfaces of rocks, when travelling with the late Sir Charles Lyell in Nova Scotia, in 1842. He noticed with the greatest interest the trails of worms, insects, and various other creatures, and the footprints of birds on the surface of the soft red tidal mud of the Bay of Fundy, and subsequently published his notes on the various markings in these deposits in his "Travels in North America," and in a paper presented to the Geological Society of London. I well remember how, in walking along the edge of the muddy shore, he stopped to watch the efforts of a grasshopper that had leaped into the soft ooze, and was painfully making a most complicated trail in his effort to escape. Sir Charles remarked that if it had been so fortunate as to make these strange and complicated tracks on some old formation now hardened into stone and buried in the earth, it might have given occasion to much learned discussion.