70 MEMOIRS OF THE CARNEGIE MUSEUM 



shown that the characters supposed to distinguish the Japanese species are 

 fallacious. In Atlantic specimens also, as well as in those from Japan, the 

 outer abdominal series of photophores ceases at about the vertical of the vent, 

 while the second series continues along the base of the anal fin. Opposite the 

 vent, the spots of the continuous series are very much reduced in size. They 

 then rapidly increase opposite the anterior portion of the anal to diminish again 

 at. once, becoming very small opposite the posterior half of the anal fin. They 

 are large again on the basal portion of the caudal peduncle, and minute on its 

 terminal portion. These oscillations in size are exactly followed in Pacific 

 material from Japan and the Hawaiian Islands. Atlantic specimens have also 

 the curved series of small photophores around the vent. Careful comparison 

 has failed to exhibit any differences. 



Genus Dasyscopelus Gtinther. 



Key to Japanese Species of Dasyscopelus. 



a. Anal photophores 7 or S in the anterior group, 2 or 4 in the posterior, 7+3 the prevaiUng number. 

 Supra-anals straight or very slightly angulated. No band of long spines along base of anal fin. 



D. orientalis. 

 aa. Anal photophores 6 to 8 in the anterior group, 5 to 8 in the posterior, 7 + 6 or 7 + 7 the prevailing 

 numbers. 

 6. Supra-anals in a straight oblique line. Adults wth the scales along the base of anal developing 



a specialized band of long spines D. spinosus. 



bb. Supra-anals distinctly angulated. No band of spines along base of anal D. asper. 



2. Dasyscopelus orientalis sp. nov. (Plate XI, fig. 1.) 



Type 67 mm. long to base of caudal, from Misaki, Sagami Bay; Alan 

 Owston, collector. (C. M. No. 6313.) 



Closely allied to D. pristilepis Gilbert & Cramer, differing in the deeper 

 body, smaller eye, more spinous scales, and in the reduction by one in the 

 number of anal photophores. In the arrangement of the photophores, the two 

 species wholly agree with each other, and also with D. spinosus and D. opalinus, 

 but the species are well distinguished by the character of the scales, number of 

 photophores, and by other details. 



Measurements in hundredths of length without caudal: Length of head 28; 

 diameter of eye 10; length of snout 5; length of longest gill-raker 5.5; interor- 

 bital width 7; length of maxillary 18; greatest depth 26; depth of caudal 

 peduncle 9; distance from tip of snout to front of dorsal 43; to front of adipose 

 fin 76; to base of ventrals 42; to front of anal 59; length of anal base 28; 

 length of pectorals 26. 



