INTRODUCTION. 



1-HE late inquiries made by M. CUVIER, LAMARCK, and other Naturalists 

 in comparative anatomy, have extended the application of the results ob- 

 tained, to the animal remains found in the various strata of our globe. Nu- 

 merous genera and species of organic beings, of whose existence we had 

 no previous idea, have been thus satisfactorily ascertained, whilst others 

 .still require persevering and patient examination; and it has been proved, 

 that by a thorough knowledge of them, greater certainty may be given to the 

 facts resulting from geological observations. 



As the environs of Bristol abound in strata replete with organic remains, I 

 was induced by these considerations to devote to them a large share of my 

 attention. The columns of the Encriuite so abundant in the black rock, {a fetid 

 mountain limestone) on the side of the river Avon, attracted my notice 

 particularly, and the sparry subrotund concretions dispersed throughout 

 the rock, made me hope that I might find in these the superior extremi- 

 ties of that animal which had been generally sought for in vain. This sus- 

 picion was soon after verified by the discovery of the fine specimen of ACTI- 

 KOOKINITES 30 DACTYLVS figured PL. n. fig. 1. and 2. A perusal of Mr. 

 PARKINSON'S work on the Organic Remains of a former World, showed 

 how much had been done, and what remained to be done, for the illustration 

 of the history of the Encririites, and M. CUVIER'S method in the identification 

 of animals by their skeletons, pointed out the mode to be pursued. I began 

 therefore to coJlect as many masses and fragments of these animals as I 

 could get. I extended my field of research gradually further around the 

 environs of Bristol, to the Transition and Mountain Limestone, the Lyas, 

 Oolite, Creensand, and Chalk : and began to arrange the specimens obtained 

 according to the strata and places where found. A few of these more perfect 

 and illustrative than the rest, enabled me to form an idea of the relative 



