has been stranded on such shores as those of the higher parts of the Firth of Forth. These Burdiehouse ichthyodorulites give positive proof that the limestone could not have originated in a lake, and the only explanation left is that of a river-bottom. But it may perhaps be objected that, after all, these fish-remains are for the most part fragmentary, and may consequently be drifted specimens, so that no conclusion as to the source of the rock can be based on their occurrence there. The imbedded land-plants confessedly came from some distance, why may not the same have been the case with the bones and scales of the river-haunting ganoid fishes? And, indeed, did we regard these fish-bones and scales merely in themselves, the argument might not perhaps be very easily answered, although the great numbers and perfect outline of the bones, teeth, and scales, afford pretty strong evidence that the owners lived and died in the locality where their remains are found. But there is a curious kind of evidence to be gleaned from the rocks around them whereby this objection can be at once set aside. In the limestone itself, and especially in some of the shales above, there occur vast numbers of small oblong coprolitic concretions of a dirty yellow or brown colour, full of scales and fragments of bone. There can be no doubt that these are the excremental remains of predaceous animals, while their great number and perfect preservation assure us that they could not have been drifted from a distance, but must rather have been deposited on the spot where we now find them. And thus we conclude that the site of Burdiehouse must have been a favourite haunt of these bone-covered fishes; that the bulkier forms, armed with pointed teeth or barbed-spines, preyed upon their humbler congeners, while these in turn may have fed on the cyprides that swarmed by millions at the bottom of the estuary. I have often detected in these coprolites the peculiarly-sculptured scales of the palæoniscus. These graceful little animals must, therefore, have died that their lordlier brethren might dine. On a survey, then, of the whole evidence from fossils, we are led to conclude that the Burdiehouse limestone was slowly elaborated at the bottom of an estuary, into which the remains of terrestrial plants were drifted from the land, while bone-covered fishes haunted the waters, and into these busy scenes huge sharks ascended from the sea to share in the decaying putrescent matter ever brought down from the interior.