G 



FISH AND FISHING IN SCOTLAND. 



as it sometimes is, by an approach on the part of the fish to its 

 spawning or foul condition. Of these three characteristic marks- 

 I shall here mention only the teeth, placing before the reader 



1st. The dentition of the trout. 



2nd. The dentition of the sea trout. 



3rd. The dentition of the salmo when adult, that is perfect,, 

 inasmuch as any animal condition can "be esteemed perfect. 



Look into the mouth of the first river or lake trout you meet 

 with of a good size, and you will see in the upper jaw or roof of 

 the mouth 1st, An uninterrupted row of teeth, extending^ 

 around nearly the whole margin of the mouth. These teeth, 

 being all of one kind, are characterized, not as in mammals or 



Fig7. Fig. 6. 



FlGS. 6 and 7. Arrangement of those teeth in the middle of the palate which anatomists 

 call vomerine. In the fresh-water trout they are arranged in a double alternating rowv 

 The large fresh-water-lake trout lose the teeth placed transversely in front (aa, figs. 6,7).j. 

 but they retain for life the double alternating row behind. 



FIG. 8. The same teeth (vomerine) in the sea trout when young. 



FIG. 9. The same teeth in the sea trout somewhat older. 



FIG. 10. The same teeth in the sea trout still older. By this time they are reduced to a 

 short single row, and this we never find in the fresh-water trout. In the true salmon 

 the transverse teeth (a) alone remain. 



in man, by different names expressive of their functions (inci- 

 sors, canine, molars) ; but by the bones supporting them, namely, 

 maxillary and intermaxillary, palatine, etc. 



2nd. Now within these, or nearer to the mesial or middle- 

 place or line of the mouth, is a second semicircular row of teeth, 

 interrupted, however, at two points. These are called vomerine 

 teeth, being carried on two bones, which anatomists generally 

 agree to call palatal bones. In the middle line of the palatal 

 and between these last described, you may now observe vomerine 

 teeth, a double alternating undulating row of teeth, extending 

 from before backwards, separated from the palatal by clear tooth- 

 less spaces, the points of the teeth being turned outwards, and. 



