7G CONTRIBUTIONS TO NORTH AMERICAN ICHTHYOLOGY — IV. 



mm. Dorsal fiu witli (usually) more than 10 rays ; pliaryngeal 



teeth numerous Catostomid^, 30. 



kJc. Gill-openings not separated by an isthmus; lower pharyn. 

 geal bones not falciform. 

 ti. Throat without barbel ; no phosijhoresccnt sjiots. 

 0. Lateral line present. 

 2). Lower jaw with a gular plate; teeth villiform; 



tins with scaly sheaths Elopid^e, 36. 



pp. Lower jaw without gular plate. 



q. Tongue with canine teeth ; maxillary extending 



beyond eye Hyodontid^, 35. 



qq. Tongue without canines. 

 r. Mouth black within ; teeth all pointed. 



AlEPOCEPHALIDv3E, 33 

 rr. Mouth pale within ; teeth on roof and floor of 

 mouth blunt and granular. .Albulid^, 34. 

 00. Lateral line obsolete. 



s. Lower jaw much shorter than upper. 



t. Mouth small, toothless ; maxillary not 



reaching beyond eye.. DoROSOMATiDiE, 38. 



it. Mouth very wide, the maxillary reaching 



much beyond eye Engraulid.e, 39. 



88. Lower jaw scarcely shorter than upper ; 



maxillary comi^ound Clupeid.e, 37. 



nn. Throat with a long barbel ; sides with phosphores- 

 cent spots Stomiatid jl, 45. 



11. —VENTRAL FINS PRESENT, THORACIC OR JUGULAR. 



A. Eyes unsymmetrical, both on the same side of the head Plkuronectid.e, 123. 



AA. Eyes symmetrical. 



S. Gill-openings in front of the pectoral fins. 



C Body more or less scaly or armed with bony jdates. 

 D. Ventral fins completely united ; gill membranes joined to the isthmus. 



GOBIID.E, 104. 

 DD. Ventral fins sei)arate. 

 E. Ventral rays I, 5. 

 F. Suborbital with a bony stay, which extends across the cheeks to or to- 

 ward the preopercle; cheeks 

 sometimes entirely mailed. 

 G. Pectoral fin with 2 or 3 lower rays detached and free. 



Teiglidje, 103. 

 GG. Pectoral fin entire. 



H. Slit behind fourth gill small or wanting. 



I. Anal spines 3 ScORPiEXiD^, 106. 



II. Anal spines obsolete CoTTiDyE, 107. 



HH. Slit behind fourth gill large Chikid^, 105. 



FF. Suborbital stay wanting ; cheeks not mailed. 



J. Spinous dorsal transformed into a lamellated sucking disk. 



ECHENEIDID,E, 70. 



J J. Spinous dorsal (if present) not transformed into a sucking disk. 

 K. Dorsal spines all or nearly all disconnected from each other. 



L. Body elongate, terete E/ACAXiDiE, 71. 



LL. Body oblong or ovate, compi-essed. 

 M. 'Caudal peduncle very slender, the fin widely forked. 



Cak^\:n'gid.e, 75. 



