530 PROCEEDINGS OF THE NATIONAL MUSEUM vol.86 



taken outside the 100-fathom line. No specimens have been taken 

 at the stations between the one near Prince of Wales Island and the 

 one near Portlock Bank. 



Named in reference to the tiny photophores. 



Family SCOPELARCHIDAE 



NEOSCOPELARCHOIDES, new genus 



Genotype. — Neoscopelarchoides dentatus, new species. 



The characters of the genus are those of the species. 



This genus is most closely related to the genera Scopelarchus and 

 Scopelarchoides . It differs from both in the proportionately slender 

 and longer body, in the lack of differentiation of the teeth on the 

 glossohyal, in the much longer caudal peduncle, and in the fact that 

 the ventrals are inserted ahead of the dorsal. From Scopelarchus 

 it is further differentiated by having the pectoral fin shorter, smaller, 

 and with much weaker rays than the stout pelvic fins. It can be 

 separated from Scopelarchoides by the normal musculature of its 

 abdominal walls which contrasts so strongly with the peculiar and 

 apparently characteristic abdominal musculature of the latter (see 

 Parr, 1929 and 1931). In common with this genus, however, it has 

 weak pectoral fins and very stout ventral fins. 



Neoscopelarchoides can be separated from the genus Benthalbella 

 by the fact that the former has teeth on the vomer and palatine while 

 the latter does not. From Promacheon the new genus differs in the 

 absence of enlarged teeth of any kind on the premaxillary, in contrast 

 to the striking dentition on the premaxillary of the former (see Weber, 

 1913, and Weber and Beaufort, 1913). 



NEOSCOPELARCHOIDES DENTATUS, new q>eciea 



Figure 67 



Types. — Holotype, a specimen 162 mm in length without caudal, 

 from station 102C, taken January 29, 1929, latitude 56°22' N., 

 longitude 145° 54' W., U.S.N. M. no. 108145, and 12 paratypes 

 ranging in length without caudal from 42 to 97 mm, taken at the fol- 

 lowing stations: 172C; 220C; 237B; 333C; 337B; 389B; 633B; 1028B; 

 lllOC; 1117B; 1134C. 



Those paratypes in the United States National Museum bear 

 numbers 108168-108176. 



Description. — (In the following description the count or proportion 

 of the holotype is given, followed by the range and average of the 

 specimens in parentheses.) Dorsal rays 7 (6 to 7; 6.9); anal rays 20 

 (17 to 21; 18.9); caudal rays 45 (43 to 46; 44.9); pectoral rays 23 

 (22 to 25; 23.5); pelvic rays 9 (9); scales in a lateral series 56 (56 to 58; 



