PLATE IX. 



FlQ. 25. The skeleton of the caudal extremity of Amia. The five small rods of bone, 

 referred to by the letters j/, are the continuation of the intemeural spines. 

 These have not been previously described, and were overlooked by Franque, 

 consequently do not appear in his figure. Taken in connection with the 

 free spines found over the anterior vertebrae of the column, these bones 

 rather lead me to believe that in the early ancestors of Amia the fin was i 

 continuous, from base of cranium to include the tail. Life size from na- 

 ture, by the author. 



112 ^^S 



