Nos. IAND2.] ANATOMY OF SCOMBER SCOMBER. i6j 



scapular it gives off, or is joined by, the supratemporal commis- 

 sure. 



As the canal traverses the lachr3^mal it has a wavy course and 

 gives off several branch canals, all of which run downward and 

 forward, downward, or downward and backward from the main 

 canal. So far as can be judged from dissections of the adult alone 

 these branch canals or tubes form parts of three dendritic sys- 

 tems, making, with the anterior terminal system of the line, four 

 systems in all in the lachrymal. 



The anterior, terminal system of the line was usually repre- 

 sented by a single tube and pore, but in certain specimens the first 

 tube posterior to this terminal one could with almost equal reason 

 be considered either as a part of the terminal system or as a part of 

 the next adjoining one. The second system was usually found as a 

 single trunk which soon separated into two tubes, each of which 

 opened on the external surface by a single pore. This system was, 

 however, sometimes found as a single tube, sometimes as two 

 separate tubes with contiguous bases, and, in the specimen shown 

 in Fig. 3, it seemed to be represented by three tubes and pores. 

 What seemed to be the third system of the line was usually repre- 

 sented by three separate tubes and pores, the two anterior tubes 

 being often united at their bases. In some fishes it was represented 

 by two tubes only. The fourth system was usually found as two 

 tubes somewhat .widely separated. 



The fifth system of the line is a single tube given off from the 

 main canal as it passes through the skin between the lachrymal 

 and suborbital bones. It is directed upward, or upward and back- 

 ward from the main canal, and is the only tube in the suborbital 

 part of the canal that is given off on its orbital side. The sixth 

 system is a single tube directed backward, or backward and up- 

 ward from the canal as it passes from the suborbital bone to the 

 lowest bone of the postorbital series. 



The seventh system is a single tube, or two tubes, given off 

 near the middle of the lowest bone of the postorbital series ; and 

 the eighth system is a single tube lying in the second bone of the 

 postorbital series near its ventral edge. The tubes of both of 

 these systems leave the main canal internal to the ventral portion 

 of the gelatine-like mass that surrounds the eve. and run down- 



