On some West-Australian Entomostraca. | 9 
fringed outside with a row of delicate bristles. The 4th 
endite is scarcely more than half as long as the stem, the 
others still shorter and not exhibiting any trace of segmentation, 
though provided on the inner edge with minutely spinulose 
ledges. Of the outer appendages, the exopodite in particular 
is considerably larger than in the 1st pair, and is of a triangular 
form, the upper corner being exserted to an acute lappet. 
In the next succeeding pairs of legs, the stem becomes 
gradually shorter, and its segmentation is at last wholly lost. 
Of the endites, the 5th somewhat increases in size, and 
assumes a lamellar character, whereas the other endites are 
much shortened and densely crowded together. Both the 
outer appendages, on the other hand, are rather fully 
developed. 
The 11th pair of legs (fig. 4) do not exhibit, in the specimen 
examined, the slightest trace of the ovisac characteristic of 
the female, both the outer appendages being quite normally 
developed, and although the specimen had not, in all pro- 
bability attained its full size, I am much inclined to believe 
that it was in reality of the male sex. 
The total number of legs I have not been able to make 
out exactly, because the posterior pairs are so extremely 
small, and lie so close together as scarcely to admit of being 
counted without dissection. 
The caudal filaments somewhat exceed half the length 
of the body, and exhibit the usual structure. In the living 
animal they were kept more or less strongly divergent, 
though they may also admit of being extended straight 
posteriorly, as indicated in the figure given by Messrs. 
Spencer & Hall. 
The colour, in the living state of the animal, was light 
yellowish, semipellucid, with a very slight greenish tinge on 
