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TRACHYCARCINUS CORALLINUS. 



27 



flagellum (which is about as long us the two distal segments of the peduncle 

 taken together^ and composed of about fifteen segments) is nearly naked. 

 The chelipeds are very unequal in size on the two sides of the body in the 

 male sex. In four specimens the right is the larger, in two the left. In 

 adult specimens the large claw is naked, smooth, and ivory-white^ like the 

 tubercles of the carapace ; the merus has a few small teeth along its upper 

 margin, most of them near the two ends of the segment, and there are also 

 a few still smaller teeth along the postero-inferior margin; the carpus is 

 inQatedj its upper margin armed with one strong tooth and denticulated 

 along its whole length ; the propodus is short and somewhat swollen, the 

 finger bent down at an obtuse angle with the lower border of the palm ; 

 there are in most specimens two or three small tubercles or teeth on the 

 superior margin of the propodus, besides a tubercular process at the articu- 



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lation of the carpus ; the dactylus is strong, down-curved, and furnished with 

 small tubercles on its upper border; both fingers are armed with large blunt 

 teeth on their opposed edges. The smaller chela is furnished with seta); it 

 is slenderer than the large claw, and has proportionally longer fingers ; it is 

 also sparsely granulated. In the female both chelipeds arc of approximately 

 equal size, and they resemble, both in size and shape, the smaller cheliped of 



the male. 



The ambulatory appendages are unarmed and clothed with coarse seta?, 

 which are most thickly set upon the dactyli. The dactyli are considerably 

 longer than the propodi, nearly cylindrical, very straight, and tipped with a 

 small, acutej horny nail. 



Dimensions of largest specimen (male) : length of carapace, 26 nun. ; 

 breadth of carapace, 27 mm.; length of larger cheliped, 50 mm.; propo- 

 dus, 20 mm.; breadth of propodus, 10.5 mm.; length of smaller cheliped, 

 24 mm. ; propodus, 9 nun. ; breadth of propodus, 4 mm. ; length of first 

 ambulatory leg, 35 mm. 



The carapace of the smallest ovigerous female measures 22x23 mm. 



The eggs are spherical and large for the size of the animal ; they vary in 

 size from one and a third to one and a half millimeters in diameter. About 



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one hundred are laid by one female. 



The depth at which this animal lives is very great for a Brachyuran. I 

 believe that the only species previously known that normally live below the 

 500 fathom line are certain species of j^thusa and JEihmina^ and Gcryon 

 qtdnqtiedens Smith. 



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