372 PROCEEDINGS OF THE NATIONAL MUSEUM. vol.48. 



jaws. These are widely spaced, are directed almost horizontally out>- 

 ward, are strongly curved, and are confined to the anterior half of 

 the cleft of the mouth, 10 or 12 in number in each jaw. The vomer 

 bears but a single tooth on one side the median line, equaling in size 

 the smaller teeth in the jaws. Palatine bones with a single close-set 

 series of short robust teeth, about 6 in number. 



Gill-membranes rather broadly joined on the median line, wholly 

 free from the isthmus, the free border on a vertical line from pos- 

 terior border of eye. Gill-slit extremely oblique, extending above 

 the pectoral for a distance equaling three-fourths width of pectoral 

 base. Gill-rakers very short and broad, much broader than high, 10 

 on anterior limb of outer arch. Sensory pores on head strongly 

 marked, especially 1 on middle of interorbital space, 1 above pos- 

 terior margin of orbit, 2 in the nasal region, and a series of 3 on 

 mandible. Several minute pores are evident on the preorbital, but 

 none are visible elsewhere on head and none on sides of body. The 

 skin is very thick and loose and renders it impossible to count the 

 rays of the vertical fins without dissection. 



The dorsal begins well behind the head, the posterior line of the 

 occiput being midway between tip of snout and first dorsal ray. As 

 in other species, the first rays are very slender and not jointed, the 

 heavy articulated rays beginning with the tenth. All the rays are 

 simple. Anterior 3 or 4 anal rays very slender, apparently not 

 jointed. 



Uniformly light in color, including the lining membrane of mouth 

 and gill-cavity. Peritoneum jet black, not visible externally through 

 the abdominal walls. On sides of head and body small dark spots 

 are hidden under the thick integument. 



Only the type known. 



LYCODAPUS ATTENUATUS, new species. 

 Plate 21, fig. 22. 



Type-specimen. — Cat. No. 75821, U.S.N.M., 163 mm. long, from 

 station 4461, in Monterey Bay, depth 285 to 357 fathoms. 



Measurements in hundredths of length to base of caudal: 



Length of head, 14.8; of snout, 4.1; diameter of eye, 3; length of 

 maxillary, 6.4; greatest width of head, 5.4; depth of head, 7.2; great- 

 est depth of body, 6.4; depth at front of anal, 5; distance from tip 

 of snout to front of dorsal, 16.3; to front of anal, 33; length of 

 pectoral, 6.5. 



Dorsal, 96; anal, 77; caudal rays not included in either case; 

 pectoral, 7. 



Body extremely attenuate, its depth less than that of head, less 

 than one-fifteenth of total length. 



Teeth coarse, in wide bands, not crowded, extensively exposed 

 when mouth is closed; a pair in inner premaxillary series near median 



