APPENDIX. 
135 
The following letter of Louis Agassiz, LL. D., 
Professor of Zoology and Geology in the Lawrence 
Scientific School of the University at Cambridge, 
together with part of a lecture delivered in Philadel¬ 
phia during the last winter, is at least evidence that 
this distinguished savan does not keep his eyes “ her¬ 
metically sealed,” or his ears closed “ against the 
entrance of information.” 
“ Dear Sir : — I return my thanks for the papers 
communicated about the existence of the so-called 
Sea-Serpent. Though I am not at all disposed to 
endorse all the reports current upon this animal, from 
the evidence I have received I can no longer doubt 
the existence of some large marine reptile allied to 
Ichthyosaurus and Plesiosaurus, yet unknown to 
naturalists. The facts mentioned to me by eye¬ 
witnesses have led me into an investigation of the 
probable relations of the great Sea-Monster, and I 
have recently expressed my opinion upon this sub¬ 
ject in connection with other matters, in a lecture 
delivered in Philadelphia last winter, of which I in¬ 
close a report, of which you may make any use you 
please. The general character of this continent, 
with its paleozoic types still alive, renders this suppo¬ 
sition very probable. 
“ With high regard, 
“ Respectfully yours, 
“ L. Agassiz. 
“ Cambridge , 15 June, 1849.” 
Extract from the Thirteenth Lecture of Pro¬ 
fessor Agassiz, delivered in Philadelphia, 
Tuesday Evening, March 20th, 1849. 
“ There is satisfactory evidence, that, during the 
deposition of the lowest strata, there were no exten- 
