xliV PROCEEDINGS OP THE GEOLOGICAL SOCIETT. [May I9OI, 



bearing on the Fish-Fauna of the Old Eed Sandstone of Scotland. 

 You have not only shown the complete divergence between the fauna 

 of the Orcadian Series and that of the Lower Old Red Sandstone 

 south of the Grampians, but you have also pointed out that in certain 

 areas the fishes in different divisions of that formation are arranged 

 in life-zones — a fact which has been of service to the field-geologist. 



Your last, and perhaps your greatest, work is your monograph on 

 che remarkable Fossil Fishes from the Silurian Rocks of the South of 

 iScotland. Your keen insight and wide knowledge of fossil ichthyology 

 enabled you to show, among other points, that the group of the 

 Heterostraci, which hitherto contained only the Pteraspidae, must 

 be considerably enlarged, and that a transition could be seen from 

 the shagreen-covered Coelolepidae tsO the plate-covered Pteraspidae. 

 You have also arrived at the conclusion that the Heterostraci, though 

 not actual Selachians, had in all probability a common origin with 

 the primitive Elasmobranchs. These results must be of the highest 

 interest to biologists. 



I have great pleasure in handing to you the Medal, together with 

 our best wishes that you may long be spared to carry on your most 

 valuable researches. 



Dr. Traquaie replied as follows : — 



Mr. President, — 



Permit me to thank the Council of the Geological Society for the 

 honour which they have this day conferred upon me, and you, Sir, 

 for the kind words which you have spoken regarding my work. 



I am much gratified to hear that some of that work has been of 

 use to the stratigraphical geologist, as it is indeed impossible for the 

 palaeontologist who has himself collected in the field, to avoid taking 

 an interest in his subject from the geological standpoint also. 



The impulse, however, which led me to take up Fossil Fishes as 

 a speciality was entirely biological. While still a boy at school 

 I broke open an iroustone-nodule containing a piece of a Palaeoniscid 

 fish, and was thereupon seized by an intense curiosity to know 

 how the bones of its head were arranged. As I did not find the 

 information that I desired in the books, I resolved some day to try 

 and work out the problem myself. Need I remark that, when in 

 due time I got fairly to work on the subject, I found that fossil 

 ichthyology presented a field sufficient to supply not only myself, 

 but many others, with original work for our lifetimes ? 



