THE SCORPJSNID^ OR SPINE-HEADS. 57 



formidable spines of different sizes^ and placed in various 

 directions ; so that their appearance is not only repulsive, 

 and even horrid^ but their handling becomes dangerous. 

 Their most prominent distinctions^ however_, from the 

 Triglida, seems not to have been perceived by M. Cuvier : 

 these_, according to our analysis, appear to consist in 

 the ventral fins being always placed considerably behind 

 the anterior part of the very broad base of the pectorals ; 

 so that, in fact, the genus Trichodon is but a modifi- 

 cation of this structure, and naturally brings it within 

 the present division. All these fishes are peculiar to the 

 tropical seas of India ; none of them are very large, nor 

 are they sought after as articles of food. The species 

 are much more numerous than those of the Triglidce, 

 and consequently present a greater diversity of forms. 

 We arrange the whole under the following genera : — 

 1 . Platycephalus, distinguished by its lengthened shape, 

 enormous eyes, and remarkably broad head. 2. Scor- 

 pcena, having the body thick, the mouth opening as in 

 ordinary fishes, and the pectoral fi.ns, which are always 

 large, often furnished with one or two detached rays, as 

 in the gurnards. 3. Synachia, where the eyes and the 

 opening of the mouth are vertical, and the dorsal fin 

 single. 4. Blepsias, having high and large dorsals, 

 which extend the whole length of the back, small and im- 

 perfect ventrals, and cirri round the mouth. And lastly, 

 Agriopus, having the mouth very small, and the high 

 dorsals of Blepsias, but with the body covered with a 

 hard tuber culated skin. 



(58.) The chain of affinities by which aU these groups 

 are connected is particularly interesting: some of these we 

 shall presently notice. Let us first, however, draw up 

 the following table, as explanatory of the analogies be- 

 tween the typical genera of the two families. 



