272 Transactions. 
lobe on the concave margin towards its base which is not found in the 
type. In the male specimen the first or upper antennae are distinctly 
shorter than the second, while in the type they were of equal length. ds 
the Enderby and Auckland Islands specimens the first antennae are co 
siderably longer than the second. The relative lengths of the pris 
in a few of the specimens in my collection are shown in the diagram given 
below, the first being represented by unbroken lines, the second by dotted 
Specimen Relative lengths of Antennae 
id Kb Ln enint erre 
j Mt Mihiwaka Ant. af 
Anti f = 
d Enderby Island Ant.2 
Ant. 
? Auckland Islands Ant. zÍ 5 
a Ant.1 
? Mt Mihiwaka Апі А м 
Аша сЕ : -= 
d Riverton Ant.z 
Ant. uf 
9 Riverton Anti{ 
Table showing relative lengths of the antennae in different specimens of Chiltonia 
lines. It will be seen that the antennae vary in length on the two sides, 
and in specimens from different localities. The generic diagnosis given b 
а 
Stebbing (1906, p. 555), which says “ Antennae 1 and 2 equal i in length," 
must be altered to “ Antennae 1 and 2 nearly equal in length." 
Fic. 1.—Chiltonia mihiwaka Chilton. 
gn?, second gnathopod of male; 
gn?*, palm of same more highly . 
magnified. 
The genus was established by Stebbing for the species now under con- 
sideration, which had been described under Hyalella. Two fresh-water 
species from Australia described by Sayce belong to Chiltonia, and other 
