96 THE MAMMOTH CAVE. 
“The general structure of the blind fishes was 
described in a former number of this journal 
(July, 1843), but a more complete description 
was given in the ‘New York Journal of Medi- 
cine’ by Tellkampf, who, in company with J. 
Miiller, of Berlin, for the first time detected the 
existence of rudimentary eyes.* They are de- 
scribed as one-twelfth of a line in diameter, 
round, black, destitute of a cornea, having an 
external layer of pigment, beneath which is a 
colorless membrane. No nerve was detected in 
connection with the eye, and the contents of the 
globe were not determined with certainty. Pro- 
fessor Owen has described the organ as a simple 
eye-speck, ‘as in the leech, consisting of a minute 
tegumentary follicle, coated by dark pigment 
which receives the end of a special cerebral 
nerve.+ Dr. John C. Dalton, Jr., has also de- 
tected the eyes, and describes them .as minute 
globular sacs containing blackish pigment, deeply 
* «New York Journal of Medicine, vol. v. p. 84, 1845. Dr. 
Dekay had previously mentioned the existence of eyes, but was 
evidently misled by some other appearance, since he states that 
eyes exist of the usual size, but are covered by the skin. He had 
not dissected them.—Fauna of New York.”—(Note by Prof. 
Wyman.) | 
+ Lectures on Comparative Anatomy, vol. ii. p. 202. See also 
his figure, p. 175. 
