EXPEDITION TO POINT BARROW, ALASKA. 141 



12. FANDALUS DAPIFER Murdoch. 



(Plate ,li gs. .) 

 1684, Pandahis dapifer, Murdoch. Proc. U. 8. Nut. Mns. vii, j). 519. 



DESCRIPTION. Length of carapace (including rostrum) contained about 2J times in total 

 length. Rostral carina beginning about the middle of the carapace, and armed with two or three 

 teeth. Rostrum exceedingly long, nearly li times the length of the carapace, slender and tapering, 

 slightly curved up, with 5 to 7 teeth on the upper edge, running only about one-third of the length 

 of the rostrum, leaving the rest unarmed to the tip. Lower edge with 4 or 5 teeth, the anterior 

 tooth a short distance from the tip. Eyes large, pyriform, and black. Peduncle of antcnnule 

 reaches about to middle of antcnnal scale, and its distal segment is about one-third the length 

 of the preceding. Internal flagellum of antennule slender, reaching nearly to end of rostrum ; 

 external about two-thirds as long as internal, much thickened nearly to the tip, where it suddenly 

 becomes slender. Antenual scale a little more than half as long as the rostrum. External maxilli- 

 peds long and slender, reaching nearly to the tip of the antcnnal scale, or about to the middle of 

 the rostrum. First pair of legs very slender, reaching to the tips of the outer maxillipeds. Second 

 (chelate) legs unequal: left very long and slender, reaching to the tip of the rostrum, carpus 

 mnltiarticulate, with about '25 joints, of which the distal twenty or so are separated by distinct 

 articulations; right leg much shorter, reaching only to the tip of antennal -scale, with a carpus of 

 about 7 joints only; distal joint of carpus in each leg equal iu length to preceding two, the rest 

 about as long as broad. Right chela a little the larger, both alike otherwise, hardly stouter than 

 the carpus ; digits equal, slightly gaping, and a little shorter than the basal portion. Third, fourth, 

 and fifth pairs of legs long and slender, reaching nearly to the tip of the antennal scale. Abdo- 

 men rounded above, except the third segment, which is compressed and keeled. This keel is 

 produced into a blunt backward-pointing hook in the male. Sixth segment once and a half as 

 long as the fifth, and equal in length to the tclsou. Telson rounded at the tip, and armed with 

 three pairs of spines. Dredged iu abundance off Point Franklin, in 13.J fathoms, August 31, 1883. 

 Museum No., 7881. 



SCHIZOPODA. 



13. MYSIS RAYII Murdoch. 



(Plate , figs. ). 

 1884, Mysis rayil, Murdoch. Proc. U. S. Nat. Mua. vii, p. 519. 



This was dredged in rather large numbers, not far from the shore, about half a mile above the 

 station, in about 5 fathoms of water, on a bottom of mud and sand mixed, August 13, 1882. Some- 

 of the females were still carrying eggs in the brood-pouches. This species belongs to the same 

 division of the genus as M. vulgaris, having the telson entire and the antennal scale fringed on both 

 sides with seta?. It may at once be distinguished from Jlf. rulgaris by the shape of the rostrum, 

 which is quadrangular, with rounded corners. 



DESCRIPTION. Rather slender, with the cephalothorax a little narrower in front than the rest 

 of the body. Carapace of medium length, exposing only the dorsal portion of the last thoracic 

 segment. Rostrum lamellar, quadrangular, with the antero-lateral angles rounded, about as broad 

 as long, reaching half the length of the ocular peduncles. Eyes not large, hemispherical ; peduncles 

 clavate, stout. Peduncle of antenuule about one-third the length of the carapace, bearing two 

 flagella, about equal to the carapace in length. Antennal scale sharply lanceolate, about as long 

 as the carapace, bearing seta? on both edges, and firmed at the tip with a sharp spine. Antenna? 

 about as long as the body. Legs medium, with tarsi of eight or nine joints. Telson about half 

 the length of the cephalothorax, lanceolate, channeled deeply above for its whole length, with apex 

 truncated, entire, and fringed with short stout seta?. TTropods long, with the inner lamina as long 

 as the telson, and the outer more than twice as long. 



Transparent, with a few arborescent black pigment spots. Length between GO and G5"" 11 . 



The species is respectfully dedicated to the commanding officer of the expedition, Lieut. P. H. 

 Ray, Eighth Infantry, U. S. A., who was superintending the dredging at the time it was taken. 

 Museum Nos., 7880 and 7892. 



