338 Horner's Geological Address. 



for instance, at p. 23, a rectification of the error committed 

 by the ingenious Hugh Miller, in describing the jaws of the 

 Coccosteus as being vertical, like those of Crustacea, and thence 

 inferring that " it seems to form a connecting link between 

 two orders of existences ;" M. Agassiz having proved that 

 they are horizontal, and move vertically, as in other true 

 fishes. Then there are four species of Sharks of the Cestracion 

 division in the Devonian rocks of Russia, and the squaloid 

 fishes of the present day offer the highest organization of the 

 brain and of the generative organs, and make in these re- 

 spects the nearest approach to the higher vertebrate classes. 



The work of Professor Owen on the fossil remains of Mam- 

 malia and Birds found in the British Islands, which has been 

 for some time in course of publication, is now completed, the 

 concluding part having been published within the last few 

 days. This valuable contribution to palaeontology, in which it 

 is the purpose of the author " to deduce from these remains, 

 by physiological comparisons, the living habits of the extinct 

 species, to trace out their zoological affinities, and to indicate 

 their geological relations," is another gift in the last year for 

 which geologists are indebted to the British Association. Pro- 

 fessor Owen, in his preface states, that the special researches 

 which have enabled him to fulfil in any degree the above- 

 mentioned design, were begun by the desire, and have been 

 carried on chiefly by the liberal aid of that body. 



The concluding part contains a very interesting and in- 

 structive introduction, which will enable the reader to follow 

 with far greater pleasure, and more fully to appreciate the 

 value of the special details which follow. He begins by point- 

 ing out that first trace of the creation of mammalian quadru- 

 peds which was discovered in the Stonesfield slate of the ooli- 

 tic series; and it was certainly a most fortunate accident which 

 brought these minute bones within the sight of a geologist. 

 It is a very remarkable circumstance, that all the researches 

 of geologists, multiplied as they have been since that dis- 

 covery was made, have not yet brought to light another frag- 

 ment of the same order of animals, throughout the vast series 

 of deposites, the immense duration of time that intervened be- 



