DECAPODS 139 



The typical Nectocrangon lar is primarily an Arctic species, and is re- 

 placed in the Aleutian Islands and the southern part of Bering Sea by a 

 species which is very closely allied, and has been heretofore 

 united with N. lar. It differs chiefly in the carinae of the sixth 

 abdominal segment terminating posteriorly in a small sharp 

 tooth or spine. The hand is more elongate, being about five 

 times or more than five times as long as its width across the palm. 



Dimensions. Female, length 73 mm., length of carapace 

 19 mm., length of hand 10 mm., width of palm 2.1 mm. (x *i)- sta- 



Type locality. Off Sitkalidak Island, Alaska, 69 fathoms Adcie" ' l! 



. Chela. 



(Albatross station 2855). 



Distribution. Bering Sea southward to Sitka and southeast coast of 

 Kamchatka ; Atlantic coast of North America from Greenland to Nova 

 Scotia, 6 to 96 fathoms. 



From Bering Sea, in lat. 59 55' oo" N., southward to Aleutian Islands 

 and Alaska Peninsula, at 65 stations of the Albatross, 21-93 fathoms. 

 Southeast coast of Kamchatka, 96 fathoms (Albatross}. 

 Aleutian Islands eastward to Sitka Harbor, 6-80 fathoms (W. H. Dall). 

 Plover Bay, Siberia, 10-25 fathoms (W. H. Dall). 



It will be noticed that the habitats of N. lar and JV. dentata overlap in 

 Bering Sea, that each is occasionally found at the extreme limit of the 

 other's range (e.g., N. lar at Kadiak and Vancouver Island, and N. 

 dentata at Plover Bay), and that N. dentata extends into deeper water. 



The species recorded from the North Atlantic by Professor S. I. Smith, 

 under the name N. lar, is, I think, identical with N. dentata. The same 

 form was collected by the Princeton Expedition at Greenland ; specimens 

 from Granville Bay are in the National Museum. 



NECTOCRANGON OVIFER Rathbun. 



Nectocrangon lar RATHBUN, The Fur Seals and Fur-Seal Islands of the North 



Pacific Ocean, Pt. ill, 556, 1899 (part). 

 Nectocrangon ovifer RATHBUN, Proc. U. S. Nat. Mus., xxiv, 892, 1902. 



In the deeper waters of Bering Sea there lives another species of Necto- 

 crangon closely allied to N. lar and N. dentata. Like them, it bears two 

 median spines on the carapace; the median crest is, however, higher, 

 and the spines more ascending ; the three spines of the anterior margin 

 above the eyes are longer and more deeply separated from each other. 

 The tubercle on the anterior surface of the eye is more prominent and 

 acute ; the eyes themselves are of greater size. The spine of the antennal 

 scale extends away beyond the blade, much more so than the allied species. 

 The pleon is relatively shorter than in N. lar and N. dentata; the median 

 carina in the female is higher ; the carinse of the sixth segment end in a 



