942 CONTRIBUTIONS TQ NORTH AMERICAN ICHTIIVOLOGY — IV. 
than long-; the hony bridge across the occiiiut but little shorter than the 
part of the head which precedes it. In A. y-grcecum the naked area is 
trapezoidal, longer than broad, and about! times the length of the snout; 
the Y is forked for more than half its length, its undivided jiart more 
than twice as long as broad, and not concave; the occipital plate is not 
half as long as the part of the head which precedes it. 
Page G29. After Astroscopus anoplus add : 
Family GUI (/>) — OPISTHOGNATHID^. 
Body oblong or elongate, low, moderately compressed, covered with 
small, cycloid scales. Lateral line present, usually incomplete, straight, 
running close to the dorsal tin. Head large, naked, the anterior profile 
decurved. Month terminal, horizontal, its cleft usually very wide, the 
maxillary extending past the eye, and sometimes considerably beyond 
the head; supplemental maxillary present; premaxillaries protractile: 
Jaws snbequal, with conical or cardiform teeth; vomer usually with a 
few teeth; palatines toothless; opercles unarmed; no suborbit-al stay. 
Pseudobranchite present. Gill-rakers rather long; gills 4, a slit behind 
the fourth; gill-membranes united, free from the isthmus. Branchios- 
tegals 0. Air-bladder present. No pyloric coeca. Dorsal fin long, con- 
tinuous, its anterior half composed of slender, flexible spines; caudal 
distinct, rounded or lanceolate; tail diphycercal; anal long, without 
distinct s})ines; ventrals separate, jugular, I, 5, the middle rays long- 
est; pectorals fan-shaped. Two genera, of about 12 species, inhab- 
iting rocky bottoms in tropical seas. Their relationships are ai)parently 
with Trachinoid forms, but they bear considerable resemblance to the 
(Ninoid Blennies. {Trachinidce, genus Opisthognathvs Giintlier, ii, 254- 
250.) 
a. Maxillary of moderate length, truncate behind Gnatiiypops, .338 (b). 
ua Maxillary of great length, prolonged in a flexible lamina behind. 
Opisthogxathus. 338 (c). 
338 (!>).— O.\ATHYP0PS Gill. 
(Gill, Proc. Ac. Nat. Sci. Phila. 186*2, 241; type Opisthognalhiis maxillosus Foey.) 
This genus includes those Opisthognathidce in which the maxillary is 
of medium length and truncate behind. (yva/9o?, jaw; uttw, below; wf, 
eye. 
©TT (b). G. maxilloseis (Poey) Gill. 
Color grayish olive, with 7 irregular A'Slpiped bars of darker, every- 
where much marbled and variegated; fins all similarly marked, the 
