PREFACE TO THE SECOND EDITION. 



The first edition of this work was published by the author in 1877. No 

 work of the kind had ever appeared, and no encouragement for the undertaking 

 had been received. The author had confidence in its value to science, and 

 published it himself. This condition of affairs is well expressed by the 

 distinguished Prof. Leo. Lesquereux, in a letter addressed to the author, while 

 the work was in press, on the 28th of March, 1877. He said: 



" Your kind favor of the 25th, and the page of prospectus of your cata- 

 logue are received. You will please allow me to say freely, that when I re- 

 ceived your first letter advising me of the preparation or publication of a 

 catalogue of the American Palaeozoic Fossils, I did not think much of a work 

 of the kind, for the reason that I knew by experience what amount of time and 

 research would be necessary for the preparation of such a work as the one you 

 were about to publish, and could not suppose that in this country, where 

 science is so generally considered under a remunerative point of view, there 

 was a naturalist disposed to make the researches you have so well done for 

 mere love of science. But after the perusal of your first proof sheets, my 

 opinion was fully reversed, and I recognized immediately the great value of 

 your catalogue, the assistance which it will afford to all the palaeontologists, 

 and the accuracy with which you have pursued the immense amount of re- 

 searches necessitated for its preparation. For what concerns myself person- 

 ally, I thank you sincerely tor this production, and I am certain that every 

 palaeontologist will do the same." 



After he had received a copy of the work, he again wrote as follows : 



" I am sincerely glad to have the whole catalogue, though I have also good 

 use of the separate copy of the botanical part, which, bound with intermixed 

 blank leaves, serves me as a very commodious referendum, especially for new 

 American species of coal plants. Your excellent, most useful catalogue, in its 

 fullness receives a degres of interest from the Introductory remarks, those on 

 the construction of systematic names, and the Geological introduction. The 

 work is, indeed, one of devotion to science. It may not bring you pecuniary 

 reward, but you will have the satisfaction to know that it has helped many, 

 and been of great use, or will be hereafter, for the advancement of palaeonto- 

 logical science. For, indeed, it is a true dictionary, and should be in the hands 

 of every American geologist." 



No testimonials of the value of the work .were ever solicited, but they 

 came, nevertheless, from all parts' of this country. and from abroad. Only a 

 few more will be selected. Prof. James. Hall, of New York, wrote: 



" You have done a valuable work, for which the thanks of every describer 



