76 CONTRIBUTIONS TO NORTH AMERICAN ICHTHYOLOGY IV. 
mm. Dorsal fm witli (usually) more than 10 rays ; pharyuf^eal 
teeth numerous Catostomid. 1 :, '.10. 
kJc. Gill-openings not separated by an isthmus ; lower pharyn. 
geal hones not falciform. 
«. Throat without barbel ; no phosphorescent si)ot8. 
0 . Lateral line present. 
j). Lower jaw with a gular plate; teeth villiform; 
tins with scaly sheaths Elopid.e, 36. 
2)p. Lower jaw without gular plate. 
q. Tongue with canine teeth ; maxillary extendiug 
beyond eye Hyodoxtidjs, 35. 
qq. Tongue without canines. 
r. Mouth black within ; teeth all pointed. 
AlEPOCEP HALIDA, 33 
rr. IMouth pale within ; teeth on roof and lloor of 
mouth blunt and granular . .Albulid.e, 34. 
00 . Lateral line obsolete. 
s. Lower jaw much shorter than upper. 
t. Mouth small, toothless ; maxillary not 
reaching be 5 mnd eye . . DoROSOMAXiDiE, 38. 
tt. Mouth very wide, the maxillary reachiug 
much beyond eye ExGKAULiDyE, 39. 
ss. Lower jaw scarcely shorter than lapper ; 
maxillary comxjound Clupeid.e, 37. 
nn. Throat with a long barbel; sides with phosxihores- 
cent spots Stomiatidje, 45. 
II.— VENTRAL FINS PRESENT, THORACIC OR JUGULAR. 
A. Eyes unsymmetrical, both on the same side of the head Pleuroxectidjs, 123. 
AA. Eyes symmetrical. 
B, Gill-openiugs in front of the pectoral fins. 
C*. Body more or less scaly or armed with bony x)lates. 
D. Ventral fins completely united; gill membranes joined to the isthmus. 
G0BIID.E, 104. 
DD. Ventral fins separate. 
E. Ventral rays I, 5. 
F. Suborbital with a bony stay, which extends across the cheeks to or to- 
ward the jireopercle ; cheeks 
sometimes eutirelj^ mailed. 
G. Pectoral fin with 2 or 3 lower rays detached and free. 
TRIGLID.E, 103. 
GG. Pectoral fin entire. 
H. Slit behind fourth gill small or wanting. 
I. Anal sxnnes 3 ScORPiENiD.E, 106. 
II. Anal siiines obsolete CoxTiDyE, 107. 
HH. Slit behind fourth gill large CniRiDiE, 105. 
FF. Suborbital stay wanting ; cheeks not mailed. 
J. Sx^inous dorsal transformed into a lamellated sucking disk. 
ECHENEIDIDiE, 70. 
JJ. 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/.^vcaxidje, 71. 
LL. Body oblong or ovate, comxjressed. 
M. Caudal XBiduucle very slender, the fin widely forked. 
CAinVXGID.E, 75. 
