xvi Journal of Comparative Neurology. 



has happened is that the ivhole of the cranium in the rei^ion of the orbit 

 has rotated on its longitudinal axis to the right side, until the two eyes, 

 instead of occupying a horizontal plane, have assumed a vertical one, 

 and the left eye is dorsal to the right. Then the dorsal fin grew for- 

 wards over the roof of the cranium, but naturally cannot define the 

 morphological right and left sides of the orbital region. Thus the 

 ocular side comprises not only the right side but a portion of the left, 

 and the true morphological median line lies between the two eyes and 

 not above them. The relation of the eyes to the skull is, notwithstand- 

 ing the rotation of the orbital region of the latter, exactly the same as 

 in a symmetrical fish, and the only differences of importance are the 

 atrophy of the anterior portion of the left frontal, and the purely sec- 

 ondary junction under the left eye of the left prefrontal and frontal." 



c. J. H. 



