Boone, Crustacea, Cruises of "Eagle" and "Ara," 1921-28 133 



Material examined : One specimen taken off Cape Malo, Panama, 

 in 300 fathoms, March, 1928, by the ''Ara." 



Distribution: This species is widely distributed in the bathy- 

 pelagic fauna of the Atlantic, Pacific and Indian Oceans. It has 

 been abundantly taken on both sides of the north Atlantic, as far 

 north as Davis Strait and Iceland, also in the Antarctic by the 

 *' Challenger" and the German South Polar Expedition and by 

 several expeditions in the tropical and south Atlantic. It was taken 

 by the Percy Sladen Trust Expedition in the southern parts of the 

 Indian Ocean. The "Challenger" took it in the Indian Archipelago, 

 also the coasts of Australia, New Zealand, the Kermadec Islands 

 and Japan. It was taken not by the "Endeavour." The "Sihoga" 

 took nine specimens in the Indo-Pacific, at five stations. Two speci- 

 mens were taken by the "Albatross" in the Gulf of Panama. It has 

 also been taken in the Mediterrranean Sea and the Adriatic, and 

 according to Dr. DeMan, the A. batei taken off Cape Lighthouse, 

 South Africa, is also A. purpurea. 



Color: Spectrum red. 



Technical description: The rostrum is four-fifths as long as the 

 carapace and is armed on the superior margin with eight, not quite 

 regularly, distributed spines in addition to the apical spine, and five 

 subequally spaced spines on the inferior margin; the rostrum is 

 moderately upcurved. There is a sharp median, longitudinal carina 

 on the second to sixth segments, inclusive, that on the second segment 

 extends only the posterior two-thirds of its length, while those on the 

 third, fourth, fifth and sixth segments each terminate posteriorly in 

 a sharp tooth, that of the third segment being decidedly the longest, 

 the sixth next, and the third and fourth spines quite small. The 

 telson is long, slender, dorsally truncate proximally and slightly 

 excavate, distally; there are seven submarginal pairs of spines along 

 the lateral border, the last two pairs being terminal. The rhipidura 

 is distinctly shorter than the telson. 



The ocular peduncle is short, dilated distally and with a blunt 

 tubercle on the inner distal margin; the cornea is pyriform, of 

 greater diameter than the peduncle and composed of many quite 

 small hexagonal facets. 



The inner antennae have the basal peduncular article deeply exca- 

 vate for the reception of the eye and fringed heavily on the margins 



