254 Professor L. Agassiz's Observations on the 



fessor Whewell, " that the gradation in form between man 

 and other animals, is but a slight and unimportant feature in 

 contemplating the great subject of man's origin. Even if we 

 had not revelation to guide us, it would be most unphilo- 

 sophical to attempt to trace back the history of man, vs^ithout 

 taking into account the most remarkable facts in his nature 

 — the facts of civilization, arts, government, speech, his tra- 

 ditions, his internal wants, his intellectual, moral, and reli- 

 gious constitution. If we will attempt such a retrospect, we 

 must look at all these things as evidence of the origin and 

 end of man's being ; and when we do thus comprehend in one 

 view the whole of the argument, it is impossible for us to 

 arrive at an origin homogeneous with the present order of 

 things. On this point the geologist may therefore be well 

 content to close the volume of the earth's physical history, 

 and open that divine record which has for its subject the 

 moral and religious nature of man." 



Observatiotis on the Blind Fish of the Mammoth Cave. By 

 Professor L. Agassiz. [In reply to a letter of inquiry 

 from Dr Silliman, senior]. 



The blind fish of the Mammoth Cave, was for the first time 

 described in 1842, in the Zoology of New York, by Dr De- 

 kay, Part 3d, page 187, under the name of " Amblyopsis 

 spelseus," and referred, with doubt, to the family of " Silu- 

 ridae," on account of the remote resemblance to my genus 

 Cetopsis. Dr J. Wyman has published a more minute de- 

 scription of it, with very interesting anatomical details, in 

 Vol. XLV. of the American Journal of Science and Arts, 

 1843, p. 94. 



In 1844, Dr Tellkampf published a more extended descrip- 

 tion, with figures, in " MuUer's Archiv," for 1844, and men- 

 tioned several other animals, found also in the cave, among 

 which the most interesting is — a Crustacean, which he calls, 

 " Astacus pellucidus," already mentioned but not described 

 by Mr Thomson, President of the Natural History Society 

 of Belfast. Both Thomson and Tellkampf speak of eyes, in 

 this species ; but they are mistaken. I have examined se- 



