Vlll LETTER OF TRANSMITTAL. 



led on from book to book in an ever- widening circle, until I 

 had all the names of fossils discovered in the Canadian prov- 

 inces. Thus I discovered that nineteenth-twentieths of our 

 Pennsylvania forms had been figured and described in the re- 

 ports of other States and Territories, some ot them fifty years 

 ago ; many of them from specimens first found in Pennsylva- 

 nia, and a few of them still peculiar to this State. During the 

 last year I have had the collections of the survey carefully ex- 

 amined in detail by Mr. Simpson, the able assistant of our most 

 distinguished American pah^ontologist, Prof. James Hall of 

 Albany, who kindly himself passed judgment on difficult de- 

 terminations, and a few new species being discovered, they were 

 drawn and described by Mr. Simpson. 



When it became a question of how the results of my prelimi- 

 nary work should be prepared for publication, I settled upon 

 an alphabetical arrangement of it as the most convenient for 

 the people of the State. What people want most are books of 

 easy reference. By placing all the names of Pennsylvania 

 fossils in alphabetical order, in the form of a glossary or dic- 

 tionary, any name given in the Reports of Progress can be 

 turned to at once and its meaning shown by a figure of the 

 thing so named. My intention was to place its proper figure 

 under every fossil name mentioned in the series of our Reports- 

 In some good measurt^ I have succeeded in doing thi^, borrow- 

 ing published figures, old and new, from every available 

 source, and having them electrotyped like woodcuts for inser- 

 tion in the text. They are therefore ail of them facsimiles; 

 and those first published a long time ago have a double value : 

 first, that of original drawings of the type specimens ; secondly, 

 that of drawings out of print, and most of them not to be ob- 

 tained for love or money, and not to be even consulted except 

 by persons who live in large cities, or at the older colleges and 

 universities. Many of the older books can not be found even 

 in large public libraries. To the public at large they are all of 

 them practically inaccessible. By reproducing them in fac- 

 simile they will be distributed to the poorest inhabitants of the 

 State, as far as an edition of the 4500 copies authorized by law 

 will serve ; and in a few years they will all get into the hands 

 of just those who most want them and can make the best use 

 of them. 



