572 



PROCEEDINGS OF THE ACADEMY OF 



[Oct., 



broad. Each corner laterally of buccal disk ends in slender -barbel 

 about equal to eye in length. Nostrils large, together, dividing 

 frenum falls about last third in snout, socket a little less than that of 

 snout and both falling within confines of interorbital space. Anterior 

 nostril simple pore with cutaneous flap behind forming valve com- 

 pletely covering slightly larger posterior nostril. Interorbital 

 broadly and slightly concave, thus supraorbital ridges slightly 



Fig. 23. — Plecostomus madeirce Fowler. (Type.) 



elevated. Very slight median occipital ridge, though hind edge of 

 latter broadly triangular. Opercle large, extremely porous. 



Gill-opening small, lateral, very oblique, and extends forward 

 only opposite last fourth of eye. Isthmus very broad, its width 

 trifle less than combined snout and eye lengths. 



Body everywhere minutely spinulose. Scutes scarcely carinate 

 on back, excepting uppermost series extending along each side of 

 dorsal base to adipose fin. Fourth or inferior lateral row of scutes 

 become well carinate below adipose fin. Nine scutes between 



