460 Edward Phelps Allis jr., 



the lateral extrascapular it gives off the supratemporal canal, a primary 

 tube arising from the canal between the squamosal and the extra- 

 scapular, and also between this last bone and the suprascapular. 

 The canal does not traverse the supraclavicular, the dorsal end of 

 that bone lying- internal to the canal as it passes from the suprascapular 

 into the first scale of the lateral line. 



In that section of the main infraorbital canal that is enclosed in 

 the hind end of the frontal, posterior to the point where the canal 

 anastomoses with the supraorbital, there is one sense organ, and it 

 is innervated by an anterior branch of the ramus oticus. In the 

 squamosal there are two organs, one anterior to the point of ana- 

 stomosis with the preopercular canal, and the other posterior to that 

 point. The anterior squamosal organ is innervated by a posterior 

 branch of the ramus oticus, and the other organ by an anterior branch 

 of what is undoubtedly the supratemporal branch of the nervus lineae 

 lateralis vagi, though it was not traced to its central origin. Two 

 other branches of this same supratemporal nerve innervated the two 

 organs of the lateral extrascapular, one of which organs lies in the 

 main infraorbital canal opposite the point of origin of the supratem- 

 poral canal, and the other in the latter canal. 



On the eyeless side of Hippoglossus the main infraorbital canal 

 differs from that on the ocular side only in that the canal begins in 

 what Traquair calls the anterior suborbital ossicle instead of begin- 

 ning in the next posterior ossicle. This so-called anterior suborbital 

 ossicle, on either side, is apparently the lachrymal of the fish. The 

 one on the eyeless, or left side is shaped much like the left lachry- 

 mal of Cole and Johnstone's figure of Pleuronectes, and has a similar 

 attachment to the left prefrontal (lateral ethmoid). The right lachry- 

 mal has an external surface outline resembling that of Pleuronectes, 

 but its middle portion is thickened internally so as to there become 

 a wedge-shaped bone, the edge of the wedge being forced in between 

 the prefrontal (lateral ethmoid) and maxillary, and the lachrymal 

 articulating, by a moveable, sliding surface, with each of the latter 

 two bones. 



There is thus, on both sides of the head of Hippoglossus, one 



