LETTER OF TRANSMITTAL. XI 



what I was told of the capacity of the electrotype process, that 

 it could not copy lithographic figures. I had confined myself 

 therefore to selecting only the wood cuts, copper plates 

 and medal-ruled figures, and had had such pencil drawings 

 made of lithographic figures as seemed indispensable. After- 

 ward I discovered by experimental trials, that the electrotype 

 process was perfectly good for making facsimiles of litho- 

 graphs, but it was then too late to introduce them into the 

 book and they had to be referred to an Appendix, except such 

 as were made in time for the last letters of the first volume. 

 The rest found their proper places in the second volume. 



Respecting the coal plant figures of Lesquereux, and Fon- 

 taine and White, published in the Coal Flora (Report P), and 

 in Report PP, they were all tinted and could not be photo- 

 graphed for the electrotype. But I considered that they had 

 already been published and distributed throughout the State, 

 and were in easy reach of all who really wanted them. I was 

 also fortunate in being permitted to use copies of many of 

 them, published as line engravings by Dr. Collett in his Re- 

 ports on the Geology of Indiana. As to Fontaine's Triassic 

 plants, published by the United States Geological Survey, they 

 too were tinted and unserviceable to me, but I was most kindly 

 allowed to have untinted proofs of them struck off in Wash- 

 ington from the original plates, and these were successfully 

 electrotyped, as may be seen in the later pages of Vol 1, and 

 throughout Vol. 2. Those whose names fall under earlier let- 

 ters can only be given in the Appendix. These are but t;xam- 

 ples of some of the obstacles I have encountered. It the Leg- 

 islature should see fit to use all the cuts which have accumu- 

 lated for a second edition of this work, the Appendix would 

 be fused back into the book to make it more useful. 



Let it be kept in mind that the intent of this Report is 

 simply to exhibit fossil forms which have been collected, or 

 seen, or described, by the geologists of the survey, in Penn- 

 sylvania, and such other fossils found in the surrounding 

 States, as have not yet been detected, but undoubtedly exist 

 in Pennsylvania, and will surely be found in Pennsylvania by 

 those who carefully and intelligently look for them. To these 

 are added rarer and sometimes exquisitely beautiful forms 

 found outside the State, but in formations which enter and 



