CRUSTACEA OF NEW ZEALAND. 243 



lobes are cousiderahly larger than in the male, the inner lobe reaching nearly to the end 

 of the ottter margin of the meros, and the outer lobe nearly to the end of the carpus ; the 

 lobes are also broader, but the armature of each is practically the same in both sexes. 

 The meros, carpus, and propodos bear fewer setse in the female, especially on the outer 

 margins, and I cannot find the central row of setae along the upper surface of the propodos 

 which was certainly present in the male specimen figured. Notwithstanding these 

 differences, there is a very close agreement ia other respects, the resemblance being greater 

 than would be imagined from a comparison of fig. 15, PI. XXII., and fig. 11, PI. XXIII. ; 

 and I wish to repeat that I am not yet certain how far the differences observed are due 

 to sex and how far to size alone. 



It is, however, in the gnathopoda that wc find the greatest difference between the 

 sexes ; and it is, perhaps, worthy of note that each gnathopod is quite different in the 

 two sexes, while in most cases in the Amphipoda one pair, at least, is the same, or ucai'ly 

 the same, in both male and female. 



The first gnaihoiiod of the female (figs. 12, 13, PI. XXIII.) has the basos rather stout, 

 widening distally, its posterior margin bearing a few setae. The ischiwii and raerOA' short, 

 subequal, each witli a few setse at the extremity on the posterior mai-gin. The carpus 

 triangular, a feAV setse on the anterior margin ; the posterior margin irregularly serrate and 

 with small tufts or transverse rows of seta^, an oblique row of four or five seta; being situated 

 on the svirfacc of the joint near the postero-distal corner. The i^ropodos is about as long 

 as the carpus and not broader than the latter at its distal end, subelliptical in outline ; the 

 anterior margin with three or four seta? and a small tuft at the base of the dactylos ; the 

 posterior margin with four short transverse rows, an oblique row of seven or eight widely 

 separated setae extending along the surface of the joint near the posterior margin ; the palm 

 is a little oblique, defined by two stout setae, its edge somewhat creuate and fringed with 

 a few small setae. The dactylos moderately stout, curved, with a few seta? on its inner 

 margin. 



The second gnathopod (figs. 11, 15) is similar in general structure to the first, but is 

 much longer and more slender. The basos, ischium, and meros are all similar to those of 

 the first gnathopod, but more slender ; the carpus is very long, much longer than the 

 propodos, narrow oblong, its posterior margin with about eight or nine tufts of setae in 

 slight serrations ; the propjodos is also oblong in outline, of the same width as the 

 carpus, both mai'gins with tufts of seta?, those on the posterior margin the longer, a very 

 distinct transverse row being situated at the base of the dactylos ; the palm is transverse, 

 defined by a small jirojection and a stout seta ; the dactylos very short. 



In the perceopoda, pleopoda, and uropoda the female does not differ from the male 

 except in the few small points already mentioned, and it is quite probable that these 

 are as much due to size as to difference of sex. I have, however, usually found the 

 telson a Little more deejoly emarginate on the hinder margin in tlie male than in the 

 female, but the difference is very slight. 



I have several times found small specimens otherwise like the ordinary female form 

 but bearing calceoli on both antennae, the calceoli being much smaller and much less 

 numerous than in the adult male, as above described, but similarly arranged. The 



SECOND SERIES. — ZOOLOGY, VOL. VI. 82 



