PERCIFORMES 



433 



Protantiyvnia, Kr. ; Miocene, Europe. Antiyonm, Lowe ; tropical seas. 

 Cupros, Lac. (Fig. 441) ; Atlantic, Mediterranean. 



SUB-TRIBE B. CHAETODONTIFORMES. The following are some of 

 the chief characters which appear in this sub-tribe : the jaws become 



FIG. 441. 



C<ijirii.i n'l'i'i-. L. A, head \vith jaws retracted, li, head with jaws protracted. C, scale, 

 enlarged. <>,-, articular ; h.m, confluent branchiostegal membranes ; d, dentary ; t, eye ; l.j, 

 lower jaw ; /./(, anterior nostril ; m, mouth ; rnb, membrane ; mr, maxilla ; pmx, premaxilla ; so, 

 anterior smootli region ; .</<, spim-s on posterior exposed region ; u.j, upper jaw ; .-, posterior 



uostiil. 



shortened, the mouth small, the palate toothless, the gill -membranes 

 confluent below ; the post- temporal becomes firmly fixed to the skull, 

 losing its forked character ; the pelvic bones meet, and tend to fuse in the 

 middle line ; the pelvic fins acquire a jugular position ; the scales become 

 modified into plates or prominent spines ; the intestine becomes long and 

 coiled ; the vertebrae are reduced to never more than twenty -five in 



28 



