ISOPODA. 65 



four specialised setae of varying length and bearing extremely delicate subsidiary 

 setas ; the outer lobe, twice the size, is armed with several stout spinous setae, each 

 having a serrated inner margin. 



The second maxilla consists of a comparatively large inner lobe, the inner margin 

 of this is rounded distally and bears several slender spinose setae, two of which, the 

 innermost, are the longest and dentate ; of the two outer lobes the innermost bears 

 three slender, tapering and minutely serrated setae, the other bears four. 



The rnaxillipeds show a broad masticatory lobe upon a short basal joint of quite 

 normal structure, the inner straight margin carries two papilliform teeth and distally 

 there are a few dentate setae ; these are very minute. The palp is five-jointed, all 

 the joints are slender and comparatively long. The epignath is long, rather spindle- 

 shaped, most swollen on the outer side, and it terminates in a blunt point almost 

 abreast of the distal border of the masticatory lobe. 



The pereiopoda are short. 



In the first the basis is a little longer than the ischium, both are slightly curved 

 and quite smooth ; the merus is short, expanded dorsally and carries a few stout setae 

 distally ; the cai-pus is a little shorter with a stout spine ventrally ; the propodus is 

 rather longer with two such spines ventrally and a few delicate setae distally ; the 

 propodus is stout with a strong claw and an equally strong though much shorter 

 accessory with a fine seta between the two. 



The second pereiopod differs in that the carpus is quite as stout as, but longer 

 than, the merus ; this latter bears one stout spine dorsally and a few fine setae 

 ventrally, the carpus bears several scattered setae, strongest dorsally. 



The third and fourth do not differ essentially ; the fifth is rather longer, and the 

 carpus bears four short and stout spinous setae ventrally and three long ones dorsally, 

 the two following are a little shorter and less conspicuously spinous. The brood 

 pouch is formed by broad lamellae on the second to the fourth appendages. 



A large number of specimens of this species were taken during our stay in Winter 

 Quarters ; they were almost entirely picked out of the sponge debris. 



Inside the 2 5 -fa thorn line. 



AUSTROSIGNUM. 



Cephalosome sub-rotund, much narrower than the first segment of the mesosome. 



Eyes small, on long slender peduncles. 



Antennae of moderate dimensions, peduncle of the second six-jointed, without an 

 accessory appendage. 



Mesosome, the three posterior segments distinctly separated from the four 

 anterior, recurved and diminishing in size. 



Metasome comprises a single independent segment and bulbous urosome often 

 prolonged as a spiuous process with minute preterminal uropoda. 



VOL. V. Q 



