674 
BULLETIN OF THE UNITED STATES FISH COMMISSION. 
Fig. 264 .—Cadorhynchus aratrum Gilbert, new species. Type. 
much more rapid in its terminal half; width at middle of snout more than half its length; vertical 
diameter of orbit contained 1.6 times in the longitudinal diameter, which equals the convex interorbital 
width, and is contained 1.7 times in snout; upper margin of orbit nearly straight; posterior nostril 
vertically elongate and weakly crescentic, the anterior a roundish pore, separated from the posterior 
by a narrow black strip of integument; two pairs of low but well-marked spinous ridges on top of 
head, the outer pair continuous with supraorbital margin, its posterior end immediately in advance 
of upper end of gill-slit; the inner pair begin in advance of middle of interorbital space, and run in 
parallel lines over occiput (in C. parallelus the inner pair of ridges converge strongly to near their 
posterior ends, then diverge) ; median rostral ridge not evident in well-preserved material; the strong 
infraorbital ridge runs from tip of snout to preopercular lobe, where it is surrounded behind and below 
by a wide, smooth membrane; upper limb of preopercle made concave by the strongly projecting 
angle; transverse width of mouth at tips of maxillaries equals half width of snout at same level, and 
equals length of maxillary ; front of mouth opposite posterior nostril or slightly behind that point, the 
end of maxillary extending to a point slightly in advance of posterior edge of pupil, its length half the 
opercle showing through; peritoneum black; abdomen externally blue-black, the color not dependent 
upon the peritoneal color; anal whitish anteriorly, becoming 1 lackish behind in adults; in young, 
the second dorsal and anal are whitish throughout; in adults, the second dorsal is black. 
Specimens were obtained at the following stations: NoS. 4116, off the northwest coast of Oahu, 
241 to 282 fathoms; 4122, off the southwest coast of Oahu, 192 to 352 fathoms; 4130, off the east coast 
of Kauai, 283 to 309 fathoms; 4132, off the east coast of Kauai, 257 to 312 fathoms. 
Coelorhyiichus aratrum, new species. Fig. 264. 
Related to C. parallelus, but differing in spination of scales and in the wholly smooth lower side j i 
of head, no scales or tubercles being present below the infraorbital ridge, except a very small patch 
on lower side of snout near its tip. 
Type, 313 mm. long, from station 3910, off the south coast of Oahu Island, depth 311 to 337 ; i 
fathoms; type, No. 51656, U. S. Nat. Mus. 
Depth of body slightly more than half length of head; D. ii, 8; V. 7; P. 18 or 19; pyloric caeca 9; ] I 
snout long, depressed, everywhere transversely convex, longitudinally a little concave, ending ante- j 
riorly in a short but definite slender spine; width of snout opposite front of orbit equal to its length 
from base of terminal spine to anterior nostril ; lateral outlines of snout convex, the narrowing being ] 
