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of its distal half, a short, tapering, terminal portion excepted, and it is fringed with fine, ciliated 

 setae; this flagellum hardly tapers as far as the end of the serrated joints. In the male of 

 A. compressipes the lower flagellum is not serrulated, and, regularly tapering, appears more 

 setiform. In the female the flagella are more equal, the loiiger upper is little longer than the 

 carapace, rostrum included, the proximal fifth part is slightly widened; the lower flagellum is 

 not serrated and tapers as regularly as the upper. 



Antennal peduncle reaching as far as the first antennular article; the flagellum measures, 

 in a female long 58 mm., 170 mm., being 3-times as long as the body; antennal scale narrow, 

 in the female just as long as the antennular peduncle, in the male a little shorter. 



External maxillipeds as in A. compressipes^ though only reaching to the anterior third 

 of the antennal scales. The chelate legs grow distinctly longer from the i^' to the 3'^, the 

 carpus of the 3"^ being longer than that of the 2"<^. The i^' legs, that reach as far as the 

 antennal peduncles, are bispinose, those of the 2""^ pair are also bispinose, those of the 3''^ 

 bear but one tooth, at the base. Fingers one and a half as long as the palm. Fourth and 

 fifth legs as in A. compressipes. In the male the carpus of the 5"^ legs reaches to the middle 

 of the antennal peduncles, the dactylus and one-fourth of the propodus extend beyond the tip 

 of the antennal scales. In the male from Stat. 312 the propodus of the s''' legs is 7 mm. long, 

 the dactylus "j ,"] mm.; there are a few short setae at the sharp extremity of the dactylus. In 

 a female, long 60 mm., from the same Station the right leg of the 5"^ pair extends with the 

 dactylus and half the propodus beyond the tip of the antennal scale, the propodus (10 mm.) 

 being distinctly shorter than the setiform dactylus which is 10,7 mm. long; of the left leg, however, 

 the propodus is 11,5 mm. long and much longer than the dactylus, that measures 7,2 mm.; in 

 another female the propodus of both legs is also longer than the dactylus. Specimens in which 

 the dactylus is longer than the preceding joint, are probably abnormal individuals. 



There are slender exopods on all the thoracic legs; epipods absent from the 3"^ maxil- 

 lipeds and the last two thoracic legs. 



The petasma of the male from Stat. 312 is symmetrical, its length is about one-third 

 the length of the carapace without the rostrum and it reaches to the coxae ot the 4"^ pair of 

 legs. The petasma is 3,3 mm. long, the distal fourth part narrows a little and it ends in a 

 pair of short horns, which stand out at right angles to the rest of the organ and each of which 

 terminates in two small teeth or hooks that are slightly curved backward; the two branches of 

 the petasma are united anteriorly, but are along their posterior edges simply apposed and these 

 edges diverge backward; at its distal extremity the width of the petasma is just one-third its 

 length. There is a sharp tooth on the sternal ridge between the i"' pleopods and a smaller on 

 that of the two following. 



The thelycum of the adult female from Stat. 302 consists of a cyathiform organ that 

 is broader anteriorly than posteriorly and that is situated between the legs of the 4'^ and of 

 the 5* pair; the somewhat thickened margins enclose the posterior half of a linguiform plate, 

 the anterior half of which is obliquely ascending between the coxae of the 4''^ legs. The anterior 

 extremity of this plate is acute, while the posterior is obtuse. Posteriorly the lateral margins 

 of the cyathiform organ pass into the posterior part of the thelycum, i.e. the posterior wall of 



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