340 ON SOME NEW GENERA AND SrECIES OF AMrilirODA. 



longitudinal, scarcely defined. Posterior gnathopoda similar in 

 shape to the anterior pair, but smaller, and with the palm directed 

 a little more transversely. Two anterior pairs of pereiopoda 

 short, stout ; third pair shorter than the fourth ; fifth much longer 

 than the fourth, slender. Fourth and fifth pairs of pleopoda with 

 stout, straight spines ; sixth pair with two or three spines like 

 those of the preceding pairs, and with two or three longer and 

 more slender spines or hairs, which are slightly curved at the 

 apex. Telson thick, truncate, armed above with two or three 

 slender spines. Length J in. 



Hah. Clark Island, Port Jackson. 



Microdeuteropus chelifer, sp. nov. (PI. XXII., fig. 3.) 



Eyes small, round. Superior antenna) nearly as long as the 

 cephalon and the first six segments of the pereion ; flagellum 

 longer than the peduncle, appendage of three articuli. Inferior 

 antenna) sub-pediform, nearly as long as the superior ; peduncle 

 stout, much longer than that of the anterior pair ; flagellum 

 shorter than the last segment of the peduncle, obscurely multi- 

 articulate. Anterior gnathopoda very large ; carpus much larger 

 than the propodos, rounded proximally, becoming broader towards 

 the distal end, its distal border transverse, armed inferiorly with 

 two prominent teeth, of which the outer is longer and sharper 

 than the inner ; propodos much narrower than the carpus, 

 articulating with less than the upper two-thirds of the distal 

 border of the latter, twice as long as broad, convex above, concave 

 below, the inferior border armed with a small tubercle near the 

 proximal end, palm not defined ; dactylos with a few spine-like 

 teeth on its inner border. Posterior gnathopoda small ; carpus 

 and propodos subequal, the latter rather the longer, the former 

 ovate ; palm undefined. Two anterior pairs of pereiopoda stout ; 

 three posterior pairs with the basa long-ovate; the third pair 

 shorter than the fourth and fifth. Posterior pleopoda very small ; 



