492 PROCEEDINGS OF THE NATIONAL MUSEUM. vol.xxiv. 
from the isthmus. Branehiostegals 6. Air bladder present. No 
pyloric ca?ca. Vertebra? large, about 27 in number. Dorsal fin long, 
continuous, its anterior half composed of slender, flexible spines, which 
pass gradually into soft rays; caudal distinct, rounded or lanceolate; 
tail not isocercal, the last vertebra expanded (27 to 84); anal long and 
low, without distinct spines; ventrals separate, thoracic I, 5, the mid- 
dle rays longest; pectorals fan shaped. Small fishes inhabiting rocky 
bottoms in tropical seas, many of them with bright markings. The 
species are almost everywhere all rarities, living about rocks in deep 
or shallow water; nowhere abundant. This group is very closely 
related to the Pseudochromididje with which Dr. Boulenger unites it, 
apparentl}^ with justice. 
a. Maxillary not of inordinate length, truncate behind, much shorter than head; 
caudal. moderate, rounded behind; body oblong, moderately compressed. 
b. Dorsal spines all simple Gnathypops, 15. 
bh. Dorsal fin with the anterior spines transversely forked or Y-shaped; maxillary 
about half length of head Stalix, 16. 
IS. GNATHYPOPS Gill. 
Gnathypops Gill, Proc. Ac. Nat. Sci. Phila., 1860, p. 241 {maxillosus) . 
This genus differs from Opisthognathus in having the maxillary of 
medium length and truncate behind, not extending to edge of opercle; 
caudal moderate, rounded behind. Dorsal spines all simple and normal. 
Species in form and habit agreeing closely with those of Opisthog- 
nathus. 
{yvados, jaw; vtio^ below; ayt/j, eye.) 
a. Dorsal, anal and caudal plain, without dark bands; dorsal rays X 14; anal II, 12; 
scales 60 hophinsi, 24. 
aa. Dorsal, anal, and caudal with dark bands; opercle without black blotch; caudal 
bordered with black; ventrals dark. D. X, 11; A. II, 10; scales 48. 
erermanni, 25. 
24. GNATHYPOPS HOPKINSI Jordan and Snyder, new species. 
Head 3i in length, depth 4|; depth of caudal peduncle 2| in head; 
eye 3i; snout 6; interorbital space 11; D. X, 14; A. II, 12; scales in 
lateral series 00. 
Body compressed, the caudal peduncle deep, dorsal outline of body 
not much elevated. Head large, broader than body, the anterior pro- 
file steep, rounded; snout short, blunt, the jaws equal. Eye large, 
the diameter greater than length of snout, placed high in head and 
anteriorly; directed obliquely upward and forward; interorbital space 
about as wide as pupil, convex. Mouth very large, the maxillary 
extending far be3^ond eye, its length 1^ in head, the upper edge with 
a small supplemental bone, the posterior end of which projects beyond 
edge of maxillary. Teeth in narrow bands on anterior part of jaws, 
