28 



First pair of legs strongly subclielate; second and third 

 similar to one another, feebly subclielate; fourth pair more 

 slender and not specially modified in the male; fifth, sixth, 

 and seventh pairs increasing progressively in length, their 

 basal joints flat and greatly produced posteriorly into a 

 rounded lobe similar to that in many Amphipoda, the lobe 

 marked off from the joint proper by a distinct ridge, posterior 

 margin of the lobe entire (fig. 10). 



Uropods short, not projecting much beyond the end of 

 the terminal segment^ outer branch slightly shorter than the 

 inner. 



Colour. — Dark slaty-grey. In some young specimens the 

 surface of the body is lighter in colour with dark pigmented 

 spots much more 'widely sejDarated from one another than in 

 the adult. 



Length of body (in curved position), about 15 mm. 

 Greatest breadth of peraeon, about 6*5 mm. 



Locality. — In hot water from Marree (Hergott) bore, 

 and in springs and streams near Coward, Central Australia. 

 Collected by Professor F. Wood Jones, Adelaide University. 



Remarks. — Although in the flattened character of the 

 peraeon and the greatly broadened basal joints of the last 

 three pairs of legs this species differs markedly from other 

 species of Phreatoicus, there seems to be a fairly close 

 resemblance in the various appendages, so that it will not 

 be necessary to give a very Retailed account of these. 



The first antenna (fig. 5) is slender, the first and third 

 joints of the peduncle similar and considerably longer than 

 the second; the flagellum is about the same length as the 

 peduncle and contains about ten joints, which bear short 

 simple setae and a few olfactory setae. The second antenna 

 (fig. 6) is considerably longer and stouter than the first; 

 the first two joints of the peduncle are short, the third 

 about twice as long as the second and subequal with the 

 fourth, the fifth longer and more slender; the flagellum is 

 subequal in length with the peduncle and contains about 

 nineteen joints, the basal ones being somewhat stout and bear- 

 ing tufts of numerous short simple setae. 



In the male the legs of the first pair (fig. 7) are strongly 

 subchelate, the propod being subtriangular and greatly 

 broadened at the base, the finger not reaching beyond the 

 straight palm. In general appearance this appendage is 

 similar to that of P. aiistralis. The second and third pairs 

 of legs (fig. 8) are similar, longer, and more slender than the 



