ISOPODA. 33 



exposed part is a narrow, rather tapering band, terminating in four stiff plumose 

 bristles ; the outer lobe is much broader and terminates in four strong teeth and some 

 half-dozen smaller pectinate ones. 



The second pair of maxillae is elongate, the inner lobe is broad, very slightly 

 tapering and curved backwards ; the inner border is fringed with fine setae and 

 distally with plumose bristles. Of the two outer lobes, the inner one is a little the 

 broadest ; both terminate in long plumose bristles. 



The maxilliped is long, divided into two equal halves as regards length. The 

 inner margin is straigh t "throughout ; the basal half tapers in a sinuous line to about 

 half its diameter ; the distal half is narrow, rounded externally, distally armed with 

 numerous and thickened plumose bristles, one papilliform tooth, and at least two of 

 these bristles occur on the inner margin. The palp is five-jointed ; the first joint is 

 small ; the second is the longest and has distally a long stout digitiform process 

 armed with setae ; the third joint is short, its process a little larger than the 

 preceding and occupies the whole joint. The fourth is twice as long and a 

 smaller process is directed forwards ; the terminal joint is slender and setose. 

 The epiguath is of moderate size, about half, the length of the basal joint and ovoid 

 in shape. 



The pereiopoda are all very much alike and of quite simple structure ; the first 

 is the shortest and stoutest, the second is a little longer, and from this onwards they 

 progressively increase in size to the last ; the increase is, however, very small and 

 chiefly concerns the first two joints. Of the first pereiopod the basis is stout, 

 constricted immediately beyond its articulation with the body ; the ischium is more 

 than half the length ; the merus is short and considerably expanded dorsally to form 

 a sort of shallow cup for the carpus ; this joint is very small, triangular in fact, its 

 dorsal margin being reduced to a minimum ; the propodus is a stout joint, third in 

 point of size, and its proximal end is in contact with the merus dorsally. The 

 dactylus is half the length, stout, and carries a curved nail distinctively marked off 

 from the joint, and immediately underneath is a small but very stout accessory claw. 

 A few setae occur distally on all the joints except the first two ; on the carpus and 

 propodus there is distally and ventrally a single stout denticulate spine, closely 

 resembling those on the ovigers of many Pycnogonids. 



In the remaining appendages the basis increases a little in length, the ischium 

 increases more, so that on the last appendage it is nearly as long as the basis. 

 The merus is larger than on the first limb, but very little larger than the carpus ; 

 both these joints are dilated distally, the former retaining its forwardly directed dorsal 

 lobe ; the propodus remains a simple cylindrical joint, and the dactylus stout and 

 curved, discoloured, and provided with a small but very stout accessory ; sometimes 

 there is a second. Setse occur distally on all the joints and occasionally elsewhere. 

 There are no denticulate spines. 



The pleopoda. The first pair comprises a very short and broad protopodite. The 



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