65. MUGILID^. 401 



M. Aual fin none; skeleton not ossified; caudal rudimentary, or not in 



the line of axis of body. 



TRACHYPTERID.E, 100. 



DD. Suborbital with bony stay. (Cottiform fishes.) 



v. Head not mailed. 



x. Slit behind fourth gill large ; body evenly 



scaled CHIRID^E, 10.~. 



xx. Slit behind fourth gill small or wanting. 

 y. Gill-membranes separate, free from 

 isthmus ; ventral fins normally 

 formed, mostly I, 5. 



SCORP^NID.E, 106. 



yy. Gill-membranes broadly joined, at- 

 tached to the isthmus or not; 

 ventral fins variously imperfect. 



COTTID.E, 107. 

 vv. Head mailed, externally bony. 



z. Ventrals few-rayed, close together; 

 last gill-slit obsolete. 



AGONID^E, 107 (&). 



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

 apart; last gill-slit large. 



TRIGLID^E, 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 co3ca numerous; subor- 

 bital with a bony stay. 

 J. Skin smooth; vertebrae very nu- 

 merous LIPARIDID/E, 109. 



6&. Skin tubercular; vertebrae rather 



few CYCLOPTERID.E, 110. 



aa. Gill-openings wide ; spinous dorsal 

 wanting; sucking -disk between 

 the ventral fins; no pyloric cceca; 

 body naked.. .GOBIESOCID^E, 111. 



FAMILY LXV. MUGILID^E. 



(The Mullets.} 



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

 cycloid scales ; no lateral line, but the 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 6. Gill-rakers long and slender. Gills 4, a slit behind 

 fourth. Psetidobranchia3 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. 16 26 



