Prof. BucKLAND on Coprolites. 231 



in that case it was aigued by Dr. Wollaston, a priori, that if the hyaenas had 

 eaten bones, we might expect to find album graecum preserved, together with 

 the fragments of bones that remained not devoured in their antediluvian dens; 

 and my immediate discovery of this substance fully verified Dr. Wollaston's 

 conjecture : the same argument extends to the case of other fossil animals that 

 swallowed bones ; the main condition is, that the osseous fasces shall have been 

 deposited in such places, and under such circumstances as would guard them 

 from destruction till they were imbedded in some protecting matrix ; this done, 

 their chemical ingredients are as indestructible as the undigested bones which 

 are preserved in the same strata with themselves. If such perishable impres- 

 sions on sand as the footsteps of tortoises and other animals, have been retained 

 and moulded on the surfaces of the strata of new red sandstone at Corncockle 

 Muir near Dumfries*, and if such fragile bodies as the eggs of aquatic birds 

 have been preserved in the lacustrine limestones of Cournon in Auvergnef, 

 why should not the indurated and semi-calcareous faeces of Ichthyosauri and 

 other voracious animals have fallen uninjured to the bottom of the sea, and 

 there becoming imbedded in mud or sand, or nascent stone, have remained 

 undisturbed and perfect unto the present hour? 



II. Coprolites in Mountain Limestone. 



The specimens engraved at Plate XXX. fig. 31 — 41. are the only ones 1 

 have seen from strata of older formation than the lias ; for my knowledge of 

 them I am indebted exclusively to Mr. J. S. Miller, who has collected a series 

 of them from the bottom of the mountain limestone at Clifton near Bristol. 

 They occur in one bed of limestone nine inches thick, between the black rock 

 limestone and the old red sandstone, and are mixed with small bones and teeth 

 of fishes, palates of at least ten kinds, spines of Balistes, and teeth of sharks, 

 and fragments of old red sandstone, and offer a case apparently analogous to 

 that of the bone-bed at the bottom of the lias ; each respectively seems to 

 indicate a period anterior to the deposition of the two great formations of the 

 mountain limestone and the lias, during which the bottom of the then existing 

 oceans received little accession of mineral matter, but was the receptacle both 

 of the indurated faeces of its voracious inhabitants, and of the bones of those 

 individuals among them that escaped violent death and consequent reduction 

 to the state of faecal balls in the stomachs of one another. 



These most ancient Coprolites in the mountain limestgne are all small, and 

 are probably varieties of Ichthyocoprus. 



* See Dr. Duncan's account of footmarks, &c. Trans. Royal Soc. Edinburgh, 1828. 



t See Croizet and Jobert's Recherches sur les Fossiles du Pay dc Dome, Disc. Prel. p. 27. 



