1886.] PROCEEDINGS OF UNITED STATES NATIONAL MUSEUM. 479 



lower pharyngeals narrower than in 

 Eleotris ; preoperclo without spine ; 

 scales very small, ctenoid, about 100 

 in a longitudinal series. Vertebrse, 

 11+13 ; teeth moderate, the outer se- 

 ries enlarged GUAViJfA, 4, 



Kh. Post-temporal bones very strongly divergent, their insertions close 



together, the distance between them 

 about f the narrow interorbital space, 

 and less than \ length of head ; top 

 of skull somewhat elevated and de- 

 clivous; interorbital area slightly con- 

 vex transversely ; lower pharyngeals 

 rather broad, the teeth bluntish ; pre- 

 operclo with partly concealed spine 

 directed downward and forward at 

 its angle ; scales moderate, ctenoid, 

 45 to 60 in a longitudinal series ; ver- 

 tebrse {pisonis) 11 + I.''} ; teetb small.* 



Eleotris, 5. 

 gg. Body very slender, elongate, the depth nine times in length to base 



of caudal ; post- temporal bones short, 

 strongly divergent, the distance be- 

 tween their insertions about equal to 

 the narrow interorbital space, or about 

 \ length of head ; top of head with a 

 strong median keel, which is highest 

 on the occipital region ; no supraoc- 

 cipital crest; preopercle without 

 spine ; mouth very oblique ; the teeth 

 small ; scales very small, cycloid. 



Erotelis, 6. 

 ee. Body naked on the anterior pa rt ; head naked ; lower jaw with four larger 



recurved teeth Gymneleotris, 7. 



aa. Ventral fins united. 



(. Dorsal fins separate free from caudal. {Gohiinoi.) 



J. Ventral disk short, iidnate to the belly; body subcylindrical, 



covered with ctenoid scales ; lips very 



thick ; upper teeth mostly small and 



movable, lower fixed ; dorsal spines 6. 



k. Teeth simple SiC YDIUM, 8. 



klc. Teeth tiifid (or bifid) Sicyopteeus, 9. 



jj. Ventral disk tree from the belly. 



I. Dorsal spines four lo eight ; eyes well developed. 



w. Teeth emarginaie,uniserial, those of the lower jaw nearly 



horizontal ; dorsal spines 6 ; scales 



large, ctenoid; gill-openiugsmoderate. 



EVORTHODUS, 10. 

 mm. Teeth simple. 



n. Maxillary normal not prolonged behind the rictus; 

 skull of the usual gobioid form, com- 

 paratively short and abruptly broad- 

 ened behind the orbits (at least in 

 typical species). 



* These characters of the skeleton are taken from Eleotris pisonis and have not been 

 verified on other species. 



