NO. 5.] ACCOUNT OF THE SPECIES. 125 



the dissection. From the very short terminal port, 5 very long and curved 

 setoe issue, 3 of which belong to the last joint, which, moreover, carries a 

 short, simple bristle. 



The posterior maxillipeds (fig. 7) are somewhat shorter than the anterior, 

 and are composed of only 2 distinctly defined joints, movably articulated 

 together. The proximal joint is rather broad and expanded, with the anterior 

 edge cut out into 3 successive rounded lobes, each carrying a remarkably 

 thick and densely hairy seta curved obliquely upwards. This seta is accom- 

 panied on the proximal lobe by another seta of much smaller size, and on 

 the distal lobe by 2 still smaller, hair-like bristles. Moreover, a ciliated, 

 anteriorly-curving seta of quite normal appearance issues from a small knob- 

 like prominence near the end of the joint anteriorly. The distal joint is 

 scarcely more than half as long as the proximal one, and much narrower, 

 exhibiting at the tip an imperfectly defined, very small terminal articulation. 

 It carries 5 anteriorly-curving, ciliated setee, diminishing in length distally, and 

 also a very small apical bristle. In structure, these maxillipeds agree very 

 closely with those in M. minor, as figured by Dr. Giesbrecht. 



The natatory legs (figs. 8 11) successively diminish in size posteriorly, 

 and exhibit a rather peculiar structure, differing considerably from that usually 

 met with in the Cyclopoida. 



The 1st pair of legs (fig. 8) have the basal part much larger than in the 

 other pairs, and lamellar in structure, its 1st joint being particularly large, 

 and provided at the end inside with a small unciliated bristle. The 2nd 

 basal joint has the inner edge somewhat bulging in the middle, and exhi- 

 biting there 3 extremely small, hair-like bristles, below which a somewhat 

 longer, but unciliated seta is attached. Both rami are 3-articuIate, though 

 the line of demarcation between the first 2 joints of the inner ramus is far 

 from being distinct. The outer ramus is considerably larger than the 

 inner, and has the 1st joint longer than the other 2 combined. At the end, 

 this joint projects outside to a short spiniform process, but has no seta 

 inside. Outside the 2nd joint is a similar, but somewhat larger spiniform 

 process, and inside a very strongly developed natatory seta. The 3rd joint, 

 which is but little larger than the 2nd, carries 4 long natatory setae, - 2 of 

 which issue from the tip; and it exhibits outside 2 successive spiniform pro- 

 cesses, which are still more produced than those of the 2 preceding joints. 



