STUDIES ON THE SEA-SHORE. 491 



families recall families belonging to ancient 

 epochs. You will find some allusion to these 

 results in my Lectures on Embryology, given 

 in my " Lake Superior/' of which I have 

 twice sent you a copy, that it might reach 

 you the more surely; but these first impres- 

 sions have assumed greater coherence now, 

 and I constantly find myself recurring to my 

 fossils for light upon the embryonic forms I 

 am studying and vice versa, consulting my 

 embryological drawings in order to decipher 

 the fossils with greater certainty. 



The proximity of the sea and the ease 

 with which I can visit any part of the coast 

 within a range of some twenty degrees give 

 me inexhaustible resources for the w r hole year, 

 which, as time goes on, I turn more and more 

 to the best account. On the other hand, the 

 abundance and admirable state of preserva- 

 tion of the fossils found in our ancient de- 

 posits, as well as the regular succession of 

 the beds containing them, contribute admi- 

 rable material for this kind of comparative 

 study. . . . 



In the summer of 1851 Agassiz was invited 

 to a professorship at the Medical College in 

 Charleston, S. C. This was especially ac- 



