134 i)i-. W. T. Caiman on a Tetresirtat 



nearly as broad as long, hind margin with low atid widely 

 spaced serrations^ 



Pleopods: all three pairs biramous, with the rami not 

 distinctly segmented. Peduncle of the first pair about six 

 times as long as broad, with a |)air of coupling-spines on 

 inner edge j exopod half as long as the peduncle, endopod 

 a little more, each bearing a few feathered setge. Peduncle 

 of second pair as long as that o£ the first^ but much stouter, 

 its width about one-fonrth of its length, bearing a pair 

 of coupling-spines ; rami slightly shorter and stouter than 

 those of first pair* Peduncle of third pair two-thirds as long 

 as that of second and about three times as long as wide, 

 with a single coupling-spine and set^e on outer and inner 

 edges ; rami short and broad, the endopod half as long as the 

 peduncle, the exopod a little less. 



Uropods: last pair more than half aa long as telson, with 

 a spine on each segment. 



Tehon curved dorsally, with an apical pair of long spines 

 on either side of a short median fissure. 

 Adult female.' — Total length 9*5 mm. 



Hardly differing in general characters from the male; 

 peduncle of antennae slightly but distinctly more slender ; 

 second gnathopod with propodus slightly stouter, a little more 

 than four times as long as wide. 



One specimen carried six eggs in the brood-cavity. 

 , Ronarhs, — Among the accepted species of the genus 

 Talitrus (Stebbing, ' Tierreich,' Gammaridea, 1906, p. 524) 

 the form here desoibed will find its place, on account of the 

 relative length of the antennules, near T. sylvaticufi, Haswell 

 (New South Wales, Victoria, and Tasmania), and T.cd/uaudi, 

 Chevreux (Seychelles, Madagascar, and hothouses in France). 

 From T. sylvaticuSj as recentl^y redescribcd by Sayce (Proc. R.. 

 Soc. Victoria, xxii, 1909, p. 30), and as represented by two 

 specimens in the British Museum, it is separated by the form 

 of the basis of the third perseopod, which, in the species 

 named, is characteristically narrowed below, with the hind 

 margin straight or slightly concave. T. alhiaudi\ as described 

 by Chevreux (Mem. Snc, zool. France, 1901, p. 389), has 

 the telson remarkably large and spinous. The most im- 

 portant distinctive characters of the new form, however, are 

 those of the second gnathopod, which in both the species 

 named is much shorter and stouter, with the propodus not 

 more than three times as long as wide, and with a projecting 

 shagreened lobe on the under side of both merus and carpus. 

 There are other characters, such as the rehtive length of the 



