Miscellaneous. 299 



short triangular cul-de-sac, the point of which reaches the posterior 

 limit of the ca^-ity of the abdomen. Stomach contracted, and mu- 

 cous membrane throwTi into longitudinal folds. Pylorus situated 

 near posterior extremity of stomach ; has a distinct valve which pro- 

 jects into cavity of duodenum ; two short pyriform csecal appendages 

 open by distinct orifices on opposite sides of intestine. Mucous mem- 

 brane of small intestine arranged in reticulated cells, which become 

 less distinct towards termination. Length of small intestine 1^ inch; 

 of large intestine | inch ; the two separated by a distinct valve. 



Liver consists of two lobes ; left extending nearly whole length of 

 abdominal cavity, right very short. Gall-bladder distinct. 



Air-bladder cordiform, deeply cleft anteriorly. 



Brain ; from anterior extremity of olfactory lobes to posterior por- 

 tion of cerebellum, 0""2J- inch. Olfactorj' lobes in contact with and 

 just in front of cerebral hemisphere, of slightly pyriform shape, and 

 giving off large ohactory nerves. Cerebral lobes nearly spherical, 

 slightly compressed on median line, where the left and right unite. 

 Optic lobes much smaller than preceding, and partly concealed by 

 the cerebellum. Cerebellum nearly spherical, slightly divided on me- 

 dian line, giving it a somewhat cordiform appearance. Fourth ven- 

 tricle completely exposed and widely open. Posterior pyramidal 

 bodies distinct, projecting over the cavity of the ventricle near its 

 middle. External to these last arise the branchio-gastric nerves. 

 Auditory sacs large ; ampullae of semicircular canals containing oto- 

 lites, one of which is of a trapezoidal shape, and nearly equalling in 

 size one of the cerebral hemispheres. The inferior optic lobes, " lobi 

 inferiores," very small, not larger than a pin's head ; in front of them 

 rests the pituitary body. No optic nerve was found. Branchio- 

 gastric and fifth pairs of nerves of the usual size. 



Internally the nostrils consist of an ovoidal cavity -j'(jth of an inch 

 in longest diameter ; olfactory membrane arranged in seven folds or 

 digitations of unequal length, and radiating from a point in the ante- 

 rior portion of the cavity. At the anterior extremity of this cavity 

 is a small orifice opening into a blind sac or canal, which passes at 

 first directly backwards and then ascends upon the upper surface of the 

 cranium. On the most careful dissection no traces of eyes were found. 



From the above description it appears that this fish, inhabiting a 

 dark cavern, is reduced, as regards its organs of vision, to a much 

 more imperfect condition than the Proteus anguinus, inhabiting the 

 subterranean caverns of Illyria, or the common mole, in both of which 

 eyes exist, although of a microscopic size. Dr. Dekay has placed 

 this fish among the Siluridce ; though, as he distinctly states, only 

 provisionally. The presence of scales and caecal appendages to the 

 pylorus, as well as the absence of ciirhi about the mouth, would seem 

 to indicate feeble affinities with the Siluridcs. The parts entering 

 into the composition of the brain, when compared with those of the 

 Pirnelodus, present many differences in the size and proportions. Its 

 true affinities cannot be well determined until an opportunity shall be 

 afforded by future dissections for the examination of its osteology. — 

 From Sillimans American Journal, July 1843. 



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