1888.] G. M. Giles— Notes on the Amphipoda of hidian Waters. 241 



architecfcural efforts, I am inclined to believe, with pellets of its own ex- 

 creta, as observed in certain kindred species by F. S. Smith (Nattire, 

 1880, p. 595). To this queer home it clings most tenaciously, and I should 

 certainly have overlooked it altogether had not my assistant, in lifting 

 some of the morsels of debris, with the view of cleaning the catch, acci- 

 dentally demolished a homestead and evicted one of the tenantrj^ ; when 

 a closer examination resulted in the discovery of a considerable number 

 of specimens. 



The animal is about 5 mm. long, and is very beautifully coloured. 

 The ground colour is a rich, deep purple, fading to nearly a burnt-sienna 

 tint towards the dorsal line, the coxal plates being darkest and free from 

 paler markings. The whole of the head and thorax is mottled with 

 patches of the brightest golden yellow, which forms a broad, but 

 somewhat irregular, band along the middle of the back, and is further 

 disposed in irregular patches over the pleura of the somites. The basi- 

 podites of the thoracic appendages are of the deepest purple, but on 

 their distal articuli the colour fades to a paler shade of the same tint. 



The head has an irregularly pentagonal outline, its anterior bor- 

 der being peculiarly vertical and straight, and without any rostrum. 

 It nearly equals in length the first two thoracic segments ; its depth 

 is but little less. The eye, which is coloured the brightest scarlet, is of 

 medium size and placed at the antero-inferior angle of the head. 



The thorax is large, forming five-ninths of the entire body length. 

 Its segments are stout, and as deep as they are long, and do not differ 

 markedly from each other in length, but the 8rd, 4th, 5th, and 6th are 

 subequal, and about J longer than the two first and the last segments. 

 The five anterior coxal plates are deeper than the corresponding 

 segments, and the 5th has the additional peculiarity of being composed 

 of two lobes, of which the anterior is as deep as, or deeper than, the coxes 

 in front of it, while the posterior lobe is very narrow and corresponds 

 in form and depth to the very small coxse of the 6th and 7th segments 

 behind it. 



The abdomen is small, forming but little more than Jrd of the 

 entire body length. Its first, second, and fourth segments are sub- 

 equal in length to the first two thoracic se<^ments, while the third is 

 subequal to a median thoracic, and the last two are very short, the pen- 

 ultimate segment being the shortest of all. In depth, the 1st abdominal 

 segment only equals the last thoracic segment and its coxae, the 2nd and 

 3rd are somewhat deeper, and the last three segments very narrow. 

 The telson is small, laminar, somewhat upturned, and of a roundedly 

 conical outline. The last three segments are armed with a few hairs 

 along the middle line. 



