INTRODUCTORY. 9 



arc not accorded to those who labour fur the mere luvc of science, 

 and thus an immense amount of details not previously accessible have 

 been accumulated. In this Supplement I shall have to summarise 

 or refer to Reports by Sir W. E. Logan, Mr Sclwyn, Dr Hunt, Pro- 

 fessor Bailey, Mr Matthew, Mr Robb, ]\Ir M'Owat, Mr Hartley, Mr 

 Scott Barlow, Mr Fletcher, and Mr Ells, embracing in all a volume 

 of matter much greater than that of my book. In addition to this, 

 local geologists and collectors have not been idle, and more especially 

 a number of important papers and reports have been published by Mr 

 Poole, Professor Hind, Dr Iloneyman, Mr Matthew, ^Ir Gilpin, Pro- 

 fessor How, Professor Chapman, Mr Paisley, and others. 



In dealing with this great mass of matter, I shall first notice the 

 modifications required in the Geological Map, and shall then refer to 

 the several formations in succession, limiting myself under each to 

 those points which seem most important either in local or general 

 geology. 



Finding by experience that the general arrangement of my book, 

 whereby the notices of fossils and of useful minerals were distributed 

 under the heads of the districts in which they principally occur, has 

 caused some difficulty in reference, and has perhaps led to the over- 

 looking of important facts by readers, I shall add a classified table c>f 

 contents which may remove this inconvenience, 



2. THE GEOLOGICAL MAP. 



In the second edition of this work it was stated that the map, though 

 greatly improved, " is to be regarded as merely a rude approximation 

 to the truth ; " and though more detailed and accurate maps of certain 

 districts have since been published, so much remains to be done, and so 

 much uncertainty exists, that I have thought it best not to alter the 

 colouring in this edition, but merely to note the changes which up to 

 the present time would seem to be indicated by new facts. 



In the map, the limits of the Triassic and Carboniferous forma- 

 tions, as they could be broadly indicated by tracing these formations 

 on a number of lines of section up to their borders, were taken as 

 the dominant boundaries, and little attempt was made to indicate the 

 subdivisions of the older Metamorphic series. Even this much in- 

 volved a large amount of labour, in time snatched from the intervals 

 of other employments, and was necessarily very imperfectly done, yet 

 these general limits, as fixed by me in 18G8, may be said still to 

 remain, the principal exceptions being the extension of the Upper 

 Coal formation along the N.-W. coast of Prince Edward Island, 



