208 EEV. T. E. E. STEBBING- ON NEW EXOTIC AMPHIPODA 



widened distally, spines on the inner surface as well as the margins ; palm oblique, with 

 a few small serratures, and having, at the end where the finger impinges, a narrow 

 cavity with spines, followed by an incurved process covered with curled markings. The 

 finger is stout, with bristles on the inner margin, and spines that project on the outer 

 margin so as to cover up the small curved nail or terminal spine and to give the appear- 

 ance of the finger ending in a slightly curved wiry brush. 



First perseopods : side-plate like that of second gnathopod, a little larger ; the leg 

 slender, first joint longest, third broader than fourth, subequal in length, fifth longer; 

 finger about half the length of the fifth joint, or less. 



Second pereeopods : side-plate excavate above posteriorly ; the leg similar to the 

 preceding. 



The three last perseopods are much alike, the first joints dilated, oval, very shallowly 

 indented behind ; the third joint is produced downwards behind ; this and the fourth, 

 which is rather longer, both terminating in a fringe of spines; the fifth joint is longer 

 than the fourth ; the finger short. 



The pleopods have nine or ten joints to each ramus. 



The first uropods have the peduncle longer than the rami, the outer ramus shorter 

 than the inner. In the second uropods the longer inner ramus about equals the 

 peduncle in length. The third uropods have the rami equal, longer than the peduncle, 

 shorter than the rami of the other pairs ; there is a group of spines near the end of 

 the peduncle, and three groups on each ramus, the end being pointed, not, as in the 

 other pairs, tipped with spines. 



The telson a rounded lobe, shorter than the short peduncles of the third uropods. 



The length is about one fifth of an inch, with a moderate inflation at the fourth 

 perseon-segment. The colour of the body, which is reported as " a deep indigo-blue, 

 appearing black when alive," is persistent in specimens which have been for months in 

 methylated spirit. The flagella of the antennae and appendages of the perseon and 

 pleon are light in colour. 



Mr. Thomson gives the following account of the habitat : — 



" Hah. Several specimens of this species were taken in a runnel of water on the 

 Obelisk (or Old-Man) range, in the interior of Otago, at a height of about 3000 feet. 

 The stream was a little thing that one could haVe dammed with the hand, and running 

 at such a slope that I can hardly imagine how the Crustacea are not washed away by 

 every shower of rain. The Old-Man range is about 80 miles from the sea. The only 

 other freshwater Amphipod found in New Zealand (excluding the subterranean forms 

 found by Chilton) is Calliope Jluviatilis, mihi, which is very common." 



P.S. — When this paper was read I had transferred the present species from the genus 

 Pherusa, Leach, in which Mr. Thomson had doubtfully placed it, to AmpMthopsis, 

 Boeck ; but on reconsideration I have preferred Mr. Thomson's view of its position, 



