MUSEUM OF COMPARATIVE ZOOLOGY. 79 



than broad ; the lamellar portion of the exopod reaches slightly beyond the 

 endopod, and the flagellilbrni is a little longer than the lamellar portion. The 

 ischium and merus in the second maxilliped (Fig. 6) are subequal in length ; 

 the propodus is about as long as the ischium and merus taken together, and 

 about half as broad as long ; the dactylus is articulated obliquely along the 

 distal end of the propodus, and is five or six times as broad as long ; the fla"el- 

 liform exopod is slender, neaily twice as long as the endopod, and multiarticu- 

 late for half its length ; the epipod bears a well-developed branchia composed 

 of two series of numerous lamella?. The endopods of the external maxillipeds 

 reach nearly to the tips of the antennal scales : the proximal segment is nearly 

 as long as the two distal, vertically comjiressed, with a knifelike mesial edge ; 

 the middle segment is very slender, cylindrical, and nearly naked ; the distal 

 segment is about two thirds as long as the middle, somewhat triquetral, very 

 slightly expanded near the middle, tapered to a point distally, and armed with 

 numerous short setae. The exopod is very slender and about three fourths as 

 long as the proximal segment of the endopod. The epipod is rudimentary, 

 scarcely longer than the breadth of the protopod, in a transverse sulcus on the 

 outer side of which it lies. 



The first four pairs of thoracic legs have exopods and epipods like the ex- 

 ternal maxillipeds, but the exopods diminish in size very rapidly posteriorly, 

 and are minute upon the fourth pair. The legs of the first pair (Fig. 7) are about 

 as long as the carapax including the rostrum and reach to or a little by the 

 tips of the antennal scales : the ischium is slightly longer than the merus, and 

 both are very slender and armed with a few small spines ; the carpus is very 

 much more slender than the merus, and about twice or considerably more 

 than twice as long, slightly enlarged at the distal extremity, and entirely naked 

 and unarmed ; the chela in the larger specimens seen is a fourth or fifth as long 

 as the carpus, considerably stouter, slightly flattened, and the digits about a 

 third of the entire length, slightly curved, and rather sparsely, clothed with 

 slender setae. The second (Fig. 8) are similar to the first, but very much 

 longer and more slender : the chela is just about as long as in the first pair, but 

 not quite as stout, while the ischium, merus, and carpus are very much longer 

 than in the first pair. The third, fourth, and fifth pairs of legs are more or less 

 broken in all the specimens seen, but are very long and slender, and are all 

 apparently longer than the second pair. The only one of these legs which is 

 complete belongs to a female 108 mm. long, and is apparently one of the pos- 

 terior pair, but is, unfortunately, detached. This leg (Fig. 9) is nearly twice as 

 long as the first pair in the same specimen, and much more slender than the 

 second even : the ischium and merus make a little more than half the entire 

 length ; the carpus is much longer than the merus, exceedingly slender, some- 

 what enlarged at the distal extremity, and entirely naked ; the propodus is 

 fully as stout as the adjacent part of the carpus, scarcely more than a tenth 

 as long, and armed with a few short setae on the dorsal side, a fascicle of longer 

 setae beneath, and a circle of very long ones about the base of the dactylus, which 

 is slightly longer than the carpus, slender, and very slightly curved. 



