1 88 MORRILL. [Vol. XI. 



surface of the dermis insinuated between the cells of the basal 

 layer of the epidermis. In some cases this investigator ob- 

 served a small terminal enlargement in the papillae, the exact 

 location of which was not indicated. 



The drawings of the dorsal surface of the brain and spinal 

 cord of Trigla adriaiica given by Tiedeman (12), together 

 with his descriptions, show considerable difference between 

 the first three spinal nerves in Trigla and Prionottis. 



The first spinal nerve in Tiigla is the largest, and arises by 

 three roots, each from the side of an enlargement. The second 

 spinal nerve arises from the fourth enlargement only, while the 

 third spinal nerve arises by two roots, one from the fifth and 

 the other from the sixth enlargement. 



The six pairs of spinal enlargements, or accessory lobes (10), 

 are small and appear to be equal in size and distinctness, which 

 is far from being true for Prionotns. 



Tiedeman (12) found that the fibers of the posterior root of 

 the third spinal nerve were generally very fine, while those of 

 the anterior root were quite coarse. Most of the nerve trunks 

 contained both kinds of fibers, or, as in the case of the branch 

 to the swimming bladder, the fibers were all of the coarser 

 variety. A similar difference in the size of the nerve fibers was 

 observed in Priouotus. 



Physiology. 



When specimens of Prionotns were placed in a tank of water 

 in the bottom of which there were several inches of sand, the 

 fish buried themselves in the sand very quickly by a rapid 

 rolling movement as they rested upon its surface. The sand 

 was thrown out on either side and settled over the surface of- 

 the body so that in most cases only the eyes, top of the head, 

 and the tip of the nose were visible. Two openings, one on 

 either side of the posterior dorsal portion of the gill-covers for 

 the escape of the water which was taken into the mouth, be- 

 came visible as the water was forced out. 



Little or no attention was generally paid to food for a few 

 moments after it was placed in the water, but as the fish swam 

 over it, as it lay upon the sand or bottom of the tank, the free 



