POLYIPXUS. 237 



Argyropelecus aflliiis sp. n. 



Argyropehcus hemigymnus G. B., 1896, Oc. Ich., PI. XXXIX., fig. 147. 



D. VII + 9 ; A. 13. 



In this species the head is longer, the body is less deep, the clavicular 

 s^-niphysis is less prominent, the caudal section is of greater comparative 

 depth, and the lanterns between the operculum and the caudal are more 

 nearly in a continuous series than in A. hemigymnus. The depth of the body 

 is about two fifths of the lengtli from the snout to the end of the caudal, 

 and the greatest depth of the caudal I'egion is nearly two thirds of that of 

 the body. Head length about one third of the distance from the snout to 

 the base of the caudal. Spines below the preopercles, the mandibles, at 

 the upper ends of the scapulars, and the spine below the ends of the 

 claviculars small. The dorsal blade resembles that of the other species of 

 the genus; it includes a similar number of spines with slightly protruding 

 ends, but has not the serrations between them as in A. caniiius. The 

 lanterns appear to be about the same in number as on A. hemigi/mnus but 

 differ in arrangement ; instead of the three very distinct and widely sepa- 

 rated groups between the ventrals and the caudal (the ventral, the anal, 

 and the subcaudal group), there is a nearly continuous series. 



station. Latitude. Longitude. Depth. 



2117 15° 24' 40" N. 63^ 31' 30'' 683 fathoms 



The outlines of this species make a considerable approach from those of 

 A. lychnis toward those of the genus Polyipnus, which, though unrepresented 

 in the collection immediately concerned in this report, has particular 

 interest here in connection with the faunal affinities, and from the fart tliat 

 besides the species hitherto recorded from the Indo-Pacific the genus is also 

 represented by an undcscribed one from the Atlantic. With the description 

 of the latter a number of items are added to the diagncsis of the genus. 



Polyipnus. 



Polyipnus Giint., 1887, "Challenger" Report, Deep Sea Fishes, 170. 



Form intermediate between that of Argyropelecus and that o? TcMhyococcus, 

 much compressed, tapering in the caudal region ; body covered by large 

 very thin .«cales. Eyes large, lateral. Mouth of medium width ; maxillary 



