84 CONTRIBUTIONS TO NORTH AMERICAN ICHTHYOLOGY IV. 
m. P.ilatine teeth none. 
n, Gill-membraues more or less joiued to the isthmus, some- 
times forming a fold across it. 
0 . First dorsal spine not elevated. 
Preorhital strongly cavernous; intestinal canal 
short ; spines of head short ; fresh 
• water Tkiglopsis, 369. 
pp. Preorhital little cauvernous; intestial canal short; 
spines of headlong; marine. (Suhgenus 
Oncocottiis) CoTTUS, 367. 
jjpp. Preorhital not cavernous; intestinal canal elon- 
gate; lateral line with a series of large 
hony idates Enophrys, 370. 
00 . First dorsal spine elevated ; skin perfectly smooth ; 
intestinal canal short. .Liocoxius, 371. 
nn. Gill-memhraues free from isthmus ; sides helow with 
oblique series of minute prickly scales; 
series of plates along hack and along 
lateral line Triglops, 372. 
mm. Palatine teeth present. 
q. Gill-membranes joined to the isthmus, sometimes 
forming a narrow fold across it. 
r. Skin perfectly smooth ; preopercular spine with 
antler-like processes; spinous dorsal 
short, entire Leptocottus, 373. 
rr. Skin with hands of rough scales ; preopercular 
spine simple; spinous dorsal long, emar- 
ginate Hemilepidotus, .374. 
qq. Gill-membranes entirely free from the isthmus. 
8. Sides of hack with a hand of rough scales; 
ventral fins very long, armed with setaj. 
Melletes, 375. 
88. Sides of hack without hand of scales. 
t. Ventrals I, 5; spinous dorsal long. 
SCORP.ENICHTHYS, 376. 
tt. Ventrals I, 3; spinous dorsal short. 
Oligocottus, 377. 
ll. Skin every where rough with villiform prickles; first dorsal 
elevated in front ; head small, with ver- 
tical cheeks. 
u. Gill-membranes free from the isthmus; 
ventrals small Blepsias, 378, 
uu. Gill-membranes united to the isthmus; 
ventrals well developed. 
Nauticiithys, 379. 
gg. Gill-opening restricted to the space above the upper edge of the base 
of the pectoral; skin everywhere with 
bifid or trifid prickles. {Ithampliocot- 
iir,(V.) 
V. Snout produced ; mouth very small ; no 
teeth on vomer or palatines; head ele- 
vated, with two bony ridges. 
Eh.\mphocottus, 380. 
