DECAPODS 75 



spines in front of middle, tip acuminate, sometimes minutely bifid. An- 

 terior margin of carapace armed with 3 spines, one supraorbital, one 

 antenna!, and one smaller, pterygostomian. Eyes large, pyriform. 



First two segments of antennules with an antero-external spine, third 

 segment less than half as long as the second and armed with a spine at 

 the middle of its anterior upper margin ; the scale at outer base over- 

 reaches the first segment. Outer flagellum reaching but little beyond the 

 rostrum ; inner flagellum twice as long. 



Antennal peduncle extending nearly to the end of the second segment 

 of the antennular peduncle. Scale oblong, tapering, shorter than the 

 carapace, tipped with a small spine which is exceeded by the blade. 

 Flagellum at least two thirds as long as the body. 



Tip of maxilliped intermediate between rostrum and antennal scale. 

 Carpal joint of first pair of feet reaching end of antepenult segment of 

 maxilliped. Second and fifth pairs of feet reaching about to end of 

 rostrum. 



Abdomen ecarinate, third segment very prominent, its hinder portion 

 extending well behind the line of the fourth segment. The sixth segment 

 is about one and two thirds as long as the fifth, and seven ninths as long 

 as the telson, which is armed with 5 or 6 spinules on each side. 



Dimensions. A female, soft shell, measures about 79 mm. in length; 

 a smaller female is 60 mm. long, carapace and rostrum 26.5 mm., rostrum 

 14.5 mm. 



Distribution. North of Unalaska, 277-351 fathoms, Albatross stations 

 33i5> 3330, 333i (type locality). 



Variations. In the male the rostrum is slenderer and more sinuous, 

 the antennal flagella considerably longer. In small specimens the rostrum 

 is relatively shorter. 



SPIRONTOCARIS VICINA Rathbun. 

 Spirontocaris vicina RATHBUN, Proc. U. S. Nat. Mus., xxiv, 895, 1902. 



Allied to S. unalaskensis. 



Female. Posterior dorsal spine at anterior third of carapace. Ros- 

 trum longer than the carapace or antennal 

 scale, concave above, dorsal spines 7 or 8, of 

 which two are on the carapace, the anterior 

 not very near the tip, inferior spines 4, tip 



r . * FIG. 29. Spirontocaris v itina. Side of 



broken oft in our specimens. Anterior carapace of 9 (x if), station 33 i6. 

 margin 3-spined, the pterygostomian spine the smallest. Eyes large, 

 pyriform. 



The antennular peduncles reach nearly to the spine of the antennal 



