Dr. A. Gunther on the Genus Trachinus. 303 



they had been named T. armatus, Schleg. He does not hesitate 

 to consider it as a species constantly differing from T. draco in the 

 ray-like arrangement of the granules on the crown of the head, 

 and in having the interorbital space more concave, the orbital 

 spines stronger, and the bands of pterygoid teeth broader. 



Those observations, as regards T. armatus, are fully confirmed 

 by an examination of the specimen in the British Museum, 

 which, probably, originates from the same source as those in 

 the Leyden Museum. But if we attach (in this case) specific 

 value to the characters mentioned, I am afraid that the species 

 T. draco will share a fate similar to that of the genus Trachinus. 

 The following are my observations on specimens from different 

 localities : — 



a. A specimen from the coast of Guinea, 7 inches long (T. 

 armatus). — The height of the body is contained 5^ times in the 

 total length. The granules on the crown of the head radiate from 

 centres ; interorbital space very narrow and concave ; spines 

 before the orbit strong. L. lat. 75. Band of ptervgoid teeth 

 8 mill, long, and If mill, broad. (PI. VIII. fig. B.)' 



b. A specimen from the island of Gomera, 9| inches long. — 

 The height of the body is contained 6^ times in the total length. 

 The granules on the crown of the head radiate from centres; 

 interorbital space not very narrow, and moderately concave; 

 spines before the orbit rather strong. L. lat. 85. Band of 

 pterygoid teeth 10^ mill, long, and \\ mill, broad. (PI. VIII. 

 fig. C.) (A specimen from Lanzarote possesses the same cha- 

 racters.) 



c. A specimen from Cannes, 8 inches long. — The height of the 

 body is contained 6^ times in the total length. The granules on 

 the head are not arranged in rays ; interorbital space not very 

 narrow, and moderately concave ; spines before the orbit rather 

 feeble. L. lat. 85. Band of pterygoid teeth 8^ mill, long, 

 and \\ mill broad. 



d. A specimen from Bahuslan (Sweden), 11" long. The height 

 of the body is yth of the total length. The granules on the 

 head are not arranged in rays; interorbital space not very 

 narrow, and but little concave ; spines before the orbit short 

 and obtuse. L. lat. 85. Band of pterygoid teeth 11^ mill, 

 long, and 1 mill, broad. (PI. VIII. fig. D.) 



Thus we see that the characters on which T. armatus is founded 

 are subject to not inconsiderable variation ; but it differs from 

 all the specimens, even from those from the Canary Islands, in 

 having a shorter body and tail. I was in hopes of finding a cor- 

 responding decrease in the number of the caudal vertebrae, which 

 at once would have settled the question of its specific distinct- 

 ness, inasmuch as in those families of fishes which have the tail 



