350 PROCEEDINGS OF UNITED STATES NATIONAL MUSEUM. 



The lobes of the metastome (labium) are very narrow and widely 

 separated at base. 



The two lobes of the first maxilla are very much as described^and 

 figured by Willemoes-Suhm in Willemoesia leptodactyla, the two lobes 

 being- very slender and strongly incurved, the anterior being the larger 

 and having at its base a minute rudimentary aiijiendage. 



The second maxilla has two small and very slender endognathal lobea 

 and a very large scaphognath, the anterior, or exognathal, portion of 

 which reaches nearly forward to the base of the antenna. 



The inner or endognathal lobes of the maxilliped are small and rudi- 

 mentary, but there is a very large and terminally bilobed lamella, ap- 

 parently representing the exoguath, which extends forward considerably 

 in front of the epistome, where its terminal lobes are somewhat upturned 

 and serve as the lower wall of a tube from the efferent brancliial open- 

 ing. This lamella is continuous posteriorly with the very large epignath 

 which extends far back into the branchial chamber. 



Both pairs of gnathopods are apparently entirely without exognathal 

 or epignathal branches. The first pair (second maxillipeds) reach 

 scarcely beyond the ischia of the second pair, and the three distal seg- 

 ments are very short, the carpus being narrow at base but expanded 

 and somewhat flattened distally, while the propodus and dactylus taken 

 together form a conical tip much shorter than the carpus. 



The second pair of gnathopods (external maxillipeds) are very slender, 

 ciliated but unarmed with teeth or spines, and, when extended, reach 

 nearly to the distal ends of the peduncles of the antennulse. The 

 ischium is about as long as the three succeeding segments and only a 

 little stouter than the merus, which is a little more than half as long, 

 and the three distal segments are subcylindrical, of about equal length, 

 and taken together are about as long as the merus. 



The terminal portion of each of the first pair of perteopods is wanting 

 in the specimen examined, but the one on the left side is perfect to near 

 the distal end of the merus. The coxa is very stout, far stouter than 

 the succeeding segments. The basis is completely anchylosed with the 

 ischium, which reaches to the tii) of the second gnathopod, is much ex- 

 panded distally, but at the same time very much compressed dorso-ven- 

 trally, and is smooth and naked. The portion of the merus which is 

 still present is about 20°™ long, is smooth and compressed like the 

 ischium, is of equal width with the ischium where it articulates with it, 

 but is slightly expanded for about half its length, then shghtly narrowed 

 distally, and is armed near the middle of the outer edge with two small 

 spines. 



The second peraeopods (figure 3) are slender, densely ciliated along the 

 edges, and reach to the tips of the peduncles of the antennae. The 

 basis is anchylosed with the rather short ischium. The merus is con- 

 siderably longer tban the iscio-basis and reaches to the edge of the 

 carapax. The carpus is a little shorter than the merus. The basal part 

 of the propodus is a very little longer than the carpus, and is flattened 



