R44 On some of the Species of Daphniade 
I shall endeavour, in describing the Australian species, to 
follow the example of so able a master. 
For the benefit of those who have not access to Mr. 
Baird’s interesting work, nor to those of Latreille, Milne 
Edwards, and others who preceded him, it may be useful 
to give at length the character of the different subdivisions 
of the Entomostraca under which the genera here to be 
mentioned are placed. 
Entomostraca. (Miill.) 
The Entomostraca (a subdivision of the large class Crus- 
tacea) may be characterized by their being all aquatic; by 
their being covered in general with a shell, or carapace, | 
which is of a horny or coriaceous texture, and formed of 
one or more pieces, in some approaching in appearance to 
a bivalve shell,—in others being in the form of a buckler, 
which completely, or in a great part, envelopes the body of 
the animal; by their having branchiz attached either to 
the feet or to the organs of mastication; by their feet 
being jointed, and all more or less ciliated ; and by their 
undergoing a regular moulting or change of shell as they 
grow, in some amounting to a species of transformation. 
The Entomostraca have been divided into three parts,— 
the Branchiopoda, the Lophyropoda, and the Peecilopoda : 
of these we are at present only concerned with the 
Brancuioropa. (Latr.) 
Character—Mouth furnished with organs fitted for 
mastication; branchiz many, attached to the feet; body 
sometimes naked, but more frequently having an envelope 
in the form of a buckler—in some enclosing only the head 
and thorax, in others the whole body; feet varying in 
number, all branchiferous; antenne two or four, jointed, 
