OF PISHES. 53 



the optic nerve ; but the organ begins at once to 

 accommodate itself, in some degree, to the exi- 

 gency of the case : the pupil diminishes its diame- 

 ter a trifle, but the fish then sees precisely, as we 

 see under water ; in reality, it is near-sighted. 

 Having no aqueous humor, the refraction produces 

 the utmost confusion for the moment. We have no- 

 ticed, that in putting a fish back into the water, after 

 having been in the air a few seconds, the vision is 

 very considerably deranged ; it swims against what- 

 ever may be in the line of its direction : indeed, 

 there does not appear to be any determinate pur- 

 pose ; but as soon as the visual organs have re-ac- 

 commodated themselves again to the water, and 

 the optic axes are restored from the distortion 

 which they received in the atmosphere, the fortu- 

 nate refugee appears again as it did before the 

 capture. 



Before leaving this subject, we cannot refrain 

 from making some observations -on the structure of 

 the eyes of the Anableps Tetrophthalmus, a scaly 

 fish, from four to ten inches in length, found at 

 Surinam, and, we believe, no where else. By 

 the politeness of Captain James Crosby, of Bos- 

 ton, and the American Consul, at Surinam, we 

 have been provided with several specimens, in a 

 fine state of preservation. As it respects the hab- 

 its of the anableps, we are not informed, but the 



