65. MUGILID^, 401 



hh. Anal fiunoue; skeleton not ossified; caudal rudimentary, or not in 



the line of axis of body. 



Tkachypteridje, 100. 

 DD. Suborbital witli bony stay. (Co^Z/brm, fishes.) 



V. Head not mailed. 



X. Slit behind fourth gill largo ; body evenly 



scaled Chirid^e, 10r». 



XX. Slit behind fourth gill small or wanting. 

 y. Gill-membranes separate, free from 

 isthmus; ventral fins normally 

 formed, mostly I, 5. 



ScOUPiENID.E, 106. 

 yy. Gill-membranes broadly joined, at- 

 tached to the isthmus or not; 

 ventral fins variously imperfect. 

 COTTID^, 107. 

 vv. Head mailed, externally bony. 



z. Ventrals few-rayed, close together; 

 last gill-slit obsolete. 



Agonid^, 107 (6). 

 zz. Ventrals 1, 4, or I, 5, usually wide 

 apart; last gill-slit large. 



Triglid^, 108. 



CC. Breast with a sucking-disk. 



a. Gill-openings narrow; spinous dor- 

 sal little developed; sucking-disk 

 formed of the united ventral fins; 

 pyloric cceca numerous; subor- 

 bital with a bony stay. 



6. Skin smooth; vertebrte very nu- 

 merous LlPARIDID^, 109. 



M. Skin tubercular; vertebris rather 



few CYCLOPTERIDiE, 110. 



aa. Gill-openings wide; spinous dorsal 

 wanting; sucking- disk between 

 the ventral fins; no pyloric cceca; 

 body naked.. .Gobiesocid^, 111. 



Family LXV.— MUGILID^. 

 {The Mullets.) 



Body oblong, more or less compressed, covered with ratber large 

 cycloid scales ; no lateral line, but tbe furrows often deepened on the 

 middle of each scale so as to form lateral streaks. Mouth small, termi- 

 nal. Jaws with small teeth, or none ; premaxillaries protractile. Gill- 

 openings wide, the membranes separate, free from the isthmus. Bran- 

 chiostegals 5 or G. Gill-rakers long and slender. Gills 4, a slit behind 

 fourth. PseudobranchiiB large. Two short dorsal fins, well separated, 

 the anterior with 4 stiff spines, the last one of which is much shorter 

 than the others; second dorsal long' r than the first, similar to anal; 

 Bull. Xat. Mus. No. IG 2G 



