ALEPOCEPHALIDAE 271 



praemaxillary and mandible, and in the smaller number of dorsal and anal rays — 14 

 to 21 instead of 27 to 30. There are five species, viz: R. giientheri (Alcock, 1892), 

 R. squamilateriis (Alcock, 1898), R. lividns (Brauer, 1906), R. nudiis (Brauer, 1906), 

 and R. watasii (Tanaka, 1909). 



Dolichopteryx longipes (Vaillant). 



Aulostoma (?) longipes, Vaillant, 1888, Exped. Sci. ' Travailkur ' et ' Talisman', Poissons, p. 340, 

 pi. xxvii, fig. 4. 



Dolichopteryx anascopa, Brauer, 1902, Sitz. Ges. Beford. Ges. Naturwiss. Marburg, 1901, No. 8, 

 p. 127; 1906, ' Valdivia' Tiefsee-Fische, p. 24, fig. 4. 



St. loi. 14-15. X. 26. 33° 50' to 34° 13' S, 16" 04' to i5°49'E. 4^ m. net, horizontal, 350- 

 400 (-0) m. : I specimen, 1 20 mm. 



St. 295. 25. viii. 27. 5° 30' 30" N, 17° 45' 00" W. Young-fish trawl, 2500-2700 m. : i specimen, 

 100 mm. 



Hab. North and South Atlantic. 



Vaillant's specimen, taken off the coast of Morocco at a depth of 1 163 m., was poorly 

 preserved and only 45 mm. in total length. It agrees very closely with that described 

 by Brauer, but there are said to be only 5 dorsal, 9 anal, and 6 pelvic rays, and the 



Fig. 3. Dolichopteryx longipes. (x i.) 



pectoral fin is shown in the figure as being comparatively short ; further, the eye is not 

 depicted as telescopic. Brauer's example, also somewhat damaged, was nearly 35 mm. 

 in length, and was taken in the Indian Ocean (west of the Cocos Islands) at a depth of 

 2400m. The two specimens obtained by the 'Discovery' are almost certainly the 

 adults of the same species, but are both very poorly preserved. They differ from the 

 smaller specimens in having a more slender body, smaller head, and the pelvic fins 

 inserted much further back. If, as I believe, all the specimens represent a single species, 

 there is a marked migration of the pelvic fins during growth. In Brauer's example 

 (35 mm.) their origin is about if times as distant from end of snout as from base of 

 caudal; in Vaillant's specimen (45 mm.) it is about twice as far; in the smaller of the 

 'Discovery' examples (100 mm.) it is 2f, and in the larger (120 mm.) t,\. A brief 

 description of these two specimens follows. 



Depth of body about 12 in the length, length of head about 4^. Minute teeth are 

 present, at least in the upper jaw. Pseudobranchiae developed. Dorsal 15 (?); last 

 ray above middle of anal. Anal 12. Pectoral 14; elongate, the third ray broader than the 



