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peduncle by one-third of the third article; flagellum robust, tapering, one and a half as long as 

 the carapace. Scaphocerite enlarged, the scale reaches to the middle of third antennular article, 

 while the terminal spine, separated by a triangular notch, hardly projects beyond the rounded 

 tip of the scale. 



External maxillipeds reaching to the middle of the carpocerite. 



Only the left cheliped is present, it is rather feeble. The merus which is unarmed, with 

 the infero-internal margin somewhat setose, is 3, 2 -times as long as its outer face is wide and 

 reaches until to the pterygostomian angle of the carapace ; it is just as long as the telson. 

 Carpus conical, with the antero-external margin notched in the middle. Chela one and a half 

 as long as the merus, entirely inverted, so that the dactylus is placed inferiorly ; the chela is 

 3,3-times as long as high in the plane of the fingers and 2,75-times as long as the latter. 

 Fingers shutting close together, the cutting-edges with a few small, acute teeth. 



Second legs rather stout. Merus 5-times as long as wide, carpus 1,3-times as long as 

 the merus. The five carpal segments are 1,14 mm., 0,28 mm., 0,28 mm., 0,28 mm. and 

 0,74 mm. long; the first segment, 4-times as long as thick at the far end, is distinctly longer 

 than the sum of the three following that are equal and just as thick as long, fifth segment 

 twice as long as thick distally, a little shorter than the sum of the three preceding. Chela 

 twice as long as the fifth segment, fingers a little shorter than the palm, which is just twice 

 as long as broad. The second legs resemble those of Bet. aequimamis according to Dana's 

 figure \\a (U. S. Explor. Exped. Crust. PI. 35), but after Thomson's description the three middle 

 carpal segments should, taken together, be equal to the first and last in length. 



The three posterior legs evidently differ from those of Bet. aeqtmnanus by the more 

 slender propodi ; the dactyli are all biunguiculate, which is also the case in Bet. aequi- 

 inanus, according to Coutiere (Les Alpheidae, 1899, p. 263, Fig. 328). The measurements 

 of the third legs are: merus 1,8; carpus i; propodus 1,8. Merus stout, 3, 5-times as long as 

 wide in the middle ; like on the meri of the fourth and fifth pair, the posterior margin bears 

 a movable spine near the proximal extremity. Carpus 3, 4-times as long as thick distally. The 

 propodus which is j u s t as long as the merus, is 8, 4-times as long as broad in the middle, 

 while in Coutiere's figure the propodus of Bet. aequimamis appears only 5-times as long as 

 broad. The propodus bears 5 or 6 very small spinules, long 0,11 mm., and 2 that are slightly 

 curved and 0,14 mm. long, at the distal extremity. Dactylus one-fourth of the propodus, 

 3-times as long as broad at its base ; the slightly bent, tapering, dorsal hook is almost 3-times 

 as long as the ventral and appears one and a half as thick at its base, notch between both 

 hooks obtuse. In the two following legs the merus appears gradually m.uch shorter. These legs 

 are nearly glabrous. 



Ova not very numerous, 1,05 — 1,1 mm. long. 



This female is 20 mm. long. 



The other specimen is much younger, 14,5 mm. long, and has lost the legs of the 

 first, the second and the fifth pair; it accords with the female but the stylocerite reaches hardly 

 beyond the middle of the second antennular article and the linear groove on the carapace 

 extends backward to beyond the middle. This specimen was sent to Professor Coutiere at 



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