Amphipod Orchestia tucurauna, Fritz Miller, 379 
QO. tucurauna arid is common on all New Zealand coasts, 
also occurs on the coasts of Chile, and, as I have pointed out 
elsewhere, numerous other Crustacea have a similar distri- 
bution—for example, the shore Isopod, Deto bucculenta 
(Nicolet), which is found in New Zealand (including the 
outlying Chatham Islands) and in Chile, South America (see 
Chilton, 1909 a, p. 602, 1909.8, p. 799, and 1915, p. 453). 
I give below a specific diagnosis, with figures of the species 
O. tucurauna, and a few additional notes on its structure. 
I wish to express my grateful thanks to my assistant, 
Miss EH. M. Herriott, M.A., for the care she has taken in 
preparing the drawings for this paper. 
Orchestia tucurauna, Fritz Miller. (Text-figs. 1-14.) 
O. tucurauna (also printed O. tueuratinga), Fritz Miller, 1864, ‘ Fiir 
Darwin, p. 54, figs. 50 & 51, and 1869, ‘ Facts and Arguments for 
Darwin,’ p. 79, figs. 50 & 51. 
O. tucurauna, Stebbing, 1906, p. 534. 
O. sulenson?, Stebbing, 1899, p. 400, pl. xxx. c, and 1906, p. 541. 
O. redmani, sp. u., Chilton, MS. 
? O. dentata, Vilhol, 1885, p. 462, pl. lili. fig. 1. 
Specific Diagnosis. 
Male.—Side-plates not deep, anterior lobe of side-plate of 
pereopod 3 much deeper than the posterior lobe. Pleon- 
segment 3 with postero-lateral angles quadrate, acute, scarcely 
produced, posterior margin with a few short sete. Eyes of 
moderate size, round, Antenna 1 not reaching to end of 
penultimate joint of antenna 2, first joint as broad as long, 
second and third each a little longer than the preceding ; 
flagellum of four to six joints, the first three being coalesced, 
subequal in length to the peduncle. Antenna 2 stout, last 
joint of peduncle longer and slightly more slender than the 
penultimate ; flagellum subequal in length to the peduncle 
and of about twenty joints, the first four or five more or less 
completely coalesced, especially in old males. Gnathopod 1 
with side-plate small, somewhat triangular, slightly produced 
anteriorly, its inferior margin bearing a few small sete; 
basal joint narrow at base, widening distally, its anterior 
surface grooved; ischium without apical process; carpus 
with prominent, narrowly rounded, distal pellucid process ; 
propod oblong, widening to the palm, and bearing distally a 
rounded pellucid process, palm not distinctly defined and 
overlapped by finger; all the joints beset with numerous 
short setee. Gnathopod 2, basal joint narrow at the base, not 
broadening greatly distally, anterior surface grooved ; carpus 
