TO 



GEORGE ORD, ESQ., IM^on of MclMs 



Sectional Library 



PRESIDENT OF THE ACADEMY OP NATURAL SCIENCES, ETC. 



My dear Friend : — 



Although you have never studied that branch of Zoology to which I have given 



so much attention, you have always taken a deep interest in my investigations and my 



memoirs on the Naiades. I feel, too, that many of us are under obligations to you for 



the encouragement you have given to our labors and the example presented by you in 



your devotion to Natural Science, as well as to polite literature, during a long life. In 



offering to you this volume, early associations are recalled — associations which commenced 



upwards of thirty-five years since, and in the infancy of the Academy at this time so 



flourishing, and over which you now preside. 



Most sincerely, 



And truly yours, 



ISAAC LEA. 



£ 



