Jordan and Evermann. Fishes of North America. 2189 



teeth villifonn, the outer scarcely enlarged ; vertebra 12 + 13 (dormitor) ; 

 skull above with conspicuous elevated ridges, one of these bounding the 

 orbit above, the orbital ridges connected posteriorly above by a strong 

 cross ridge; a sharp longitudinal ridge on each side of the occipital, the 

 two nearly parallel, the post-temporals being attached to the pos- 

 terior ends. Insertions of post-temporals widely separated, the dis- 

 tance between them greater than the rather narrow interorbital width ; 

 the post-temporal bones little divergent; top of head depressed, both 

 before and behind the cross ridge between eyes ; a flattish triangular 

 area between this and the little elevated supraoccipital region; pre- 

 opercle without spines ; lower pharyngeals with slender, depressiblo 

 teeth, and without lamelliform appendages ; scales of moderate size, 

 ctenoid. PHILYPNUS, 801. 



dd. Vomer without teeth ; isthmus broad ; gill openings scarcely extending for- 

 ward below to posterior angle of preopercle ; skull without crests. 

 e. Body scaly, both anteriorly and posteriorly. 



/. Lower pharyngeal teeth staff and blunt; the bones with an outer 

 series of broad flexible lamelliform appendages, which are 

 rudimentary gill filaments; body short and elevated; teeth 

 slender, those in the outer row scarcely larger, and movable ; 

 top of head without raised crests, flattish, its surface uneven; 

 post-temporal bones rather strongly diverging, the distance 

 between their insertions about J the broad flattish interorbital 

 space; no spine on preopercle or branchiostegals; scales large, 

 ctenoid. Species herbivorous. DOBMITATOR, 802. 



ff. Lower pharyngeals normal, subtriangular, the teeth stiff, villi- 

 form, no lamelliform appendages ; scales of moderate or small 

 size ; body oblong or elongate. 



g. Body moderately robust, the depth 4 to 5 times in the length 

 to base of caudal ; scales ctenoid ; cranium without dis- 

 tinct median keel ; a small supraoccipital crest. 

 h. Post-temporal bones little divergent, not inserted close 

 together, the distance between their insertions 

 greater than the moderate interorbital space, or 

 3f in length of head ; top of skull little gibbous ; 

 lower pharyngeals narrower than in Eleolris; pre- 

 opercle without spine ; scales very small, about 110 

 in a longitudinal series. Vertebrte 11 + 13 ; teeth 

 moderate, the outer series on lower jaw enlarged. 



GUAVINA, 803. 



hh. Post-temporal bones very strongly divergent, their in- 

 sertions close together, the distance between them 

 about f the narrow interorbital space, and less than 

 f length of head; top of skull somewhat elevated 

 and declivous ; interorbital area somewhat convex 

 transversely ; lower pharyngeals rather broad, the 

 teeth bluntish; preopercle with partly concealed 

 spine directed downwards and forward at its angle ; 

 scales moderate, 45 to 60 in a longitudinal series ; 

 vertebrae (pisonis) 11 -f 15 ; teeth small. 



ELEOTBIS, 804. 

 gg. Body very slender, elongate, the depth 8 to 9 times in length 



to base of caudal ; scales very small, cycloid. 

 i. Preopercle with a partly concealed antrorse hook at its 

 angle; caudal with numerous accessory rays at 

 base. ALEXURUS, 805. 



