764 PROCEEDINGS OF THE NATIONAL MUSEUM. 



projecting be^'ond the short anal and dorsal rays; the lower pectoral 

 rays are inconipletel\' united with the upper part of the lin and are 

 prolonged; ventrals reduced to a simple filament, inserted behind the 

 humeral symphysis, and somewhat distant from each other. Lateral 

 line incomplete, close to the dorsal profile. A true deep-sea form. 

 {Pteroix. Onnx.) 



14. PTEROIDONUS QUINQUARIUS Giinther. 



Pteroidonus quinquarius Gunther, Deep-Sea Fishes Challenger, 18S7, ji. 106; Deep 

 Sea of Japan, Station 235, 565 fathoms. 



D. 99; A. S7; P. 15-5; V. 1; C. 5; B. 8; 35 scales transversely above 

 vent; eye, 7 in head; caudal, 7i. 



Body elongate, compressed, its depth being less than the length of 

 the head, which equals the distance between the vent and the root of 

 the pectoral fin. Head not much deeper than broad, its depth equal 

 to the length of its postorbital portion and flat above; eye small, with- 

 out orbital fold, much shorter than snout, lateral, and situated imme- 

 diately below the upper profile of the head; no spines about orbit; 

 snout broad, rather depressed, overlapping the lower jaw; mouth wide, 

 somewhat oblique, the much-dilated posterior extremity of the maxil- 

 lary extending ])ackward beyond the orbit; preorbital region narrow, 

 inframaxillary styliform; teeth in villiform bands, the bands of the 

 vomer and palatines verv narrow; vomerine band A -shaped; nostrils 

 rather distant from each other, open, the posterior the larger, imme- 

 diately in front of the upper part of the eye, the anterior close to the 

 end of the snout; the interorl)ital space more than twice the eye; pre- 

 operculum with a rounded angle which is armed with 3 very short and 

 weak spines; opercular spine moderately strong and straight; the bones 

 of the head are thin, with shallow muciferous cavities. Gill-membranes 

 entirely separate. 



Nearly the entire head, even the dilated extremity of the maxillar}^ 

 and the glossohyal region, are covered with small scales; the scales are 

 small, thin, smooth, and adherent. 



Dorsal begins a short distance behind root of pectoral, rather low, 

 the rays inclosed in a scaly skin at base, and has its last and shortest 

 rays connected with caudal by a membrane; anal similar to dorsal l)ut 

 lower; pectoral with broad base, elongate, posterior margin rounded, 

 and as long as head without snout; the 5 detached rays are somewhat 

 stronger than the other rays; they form at the base one continuous 

 series with the remainder of the fin, and therefore do not seem to pos- 

 sess a separate action; the uppermost ray is the longest, not quite 

 twice as long as the fin, the others gradually decreasing in length; 

 ventrals very feeble simple filaments, only half as long as the pectoral, 

 somewhat distant from each other and inserted opposite to the hind 

 margin of the preoperculum; the tail tapers almost to a point. The 



