472 MARGUERITE HENRY. 
This form differs from A. avirostris in the peculiar shape 
of the posterior edges and the absence of denticles on 
postero-ventral angles. It also differs in the position of the 
ocellus and the length of the antennules. 
Specific Characters.—Viewed laterally, the carapace has 
a truncated oval form; the dorsal margin is slightly arched, 
the ventral edges of the valves fairly straight, forming an 
abrupt angle with the anterior edges, posterior edges 
sinuated, no denticles present on the postero-ventral angle, 
shell obliquely striated. Head bent down terminating ina 
blunt rostrum. Ocellus situated nearer the tip of the 
rostrum than to the eye. Antennules reaching beyond 
the tipof the rostrum. Tail-piece long and narrow, eleven 
comb-like bundles of lateral spines present; end-claws long 
with two denticles one at the base and one at the middle 
with a row of spinelets between the two. Length of the 
adult female 0°59 mm. 
Locality.—Kendall, collected in November. Type speci- 
men in the Australian Museum, No. P 4329. 
ALONA WALLACIANA Sp. 0. 
(Plate XLI, figs. 7, 8.) 
The length of the largest specimen examined is 0°49 mm. 
The carapace is compressed, and, viewed laterally, has an 
oblong oval form; the greatest height 0°31 mm. is slightly 
in front of the middle. The dorsal margin is evenly arched; 
the ventral edges of the valves are almost straight; the 
posterior edges slightly arcuate, evenly rounded off at the 
corners. , 
The head is hood-like, its dorsal margin forming a con- 
tinuous, even curve with that of the carapace; inferiorly 
the head terminates in an acute rostrum which does not 
reach ventrally as far as the inferior edges of the valves. 
