REVIEWS. 
77 
The Acalypterce are divided by Mr. Walker into the sub-families Helo - 
myzides , Borhorides , Lauxanides , Ortalides , Sepsides, Loxocerides , Psili- 
des , Oscinides , Geomyzides , Phytomyzides , and Hydromyzides. We find 
nothing to censure in this division generally : in particular, the separation 
of the Helomyzides , Lauxanides , Ortalides , and Sepsides from the remain¬ 
ing sub-families, in which the subcostal and mediastinal veins are united, 
and not separated as in these, has an appearance of reason; but, unfortu¬ 
nately, the union of these veins is not always so complete as the author seems 
to assume. The least satisfactory of these groups is the sub-family Helomy- 
zides , the contents of which are rather heterogeneous. Of the genera ad¬ 
mitted into it, Scatophaga and Cordylura approach more to the Antkomy- 
ides ; while Dorycera and Tetanops come nearer to the Ortalides , and might 
even be better placed among these. Burkina belongs to the Oscinides ; 
Coelopa stands nearer to the Borhorides than to the rest of the Helomyzi¬ 
des, and would be better placed among the former, a change which would 
probably draw Orygma also after it. These extraneous elements being 
removed, there would remain still united under the Helomyzides but two 
groups, having for their types respectively Helomyza and Tetanocera , 
which might accordingly be denominated Helomyzides and Tetanocerides. 
We have nothing to object to the conjunction of Saltella with the Sepsides , 
notwithstanding the difference of veining of the wings, as the structure of the 
mouth tends to unite them. More questionable is the place assigned to 
Calohata in the same sub-family : of this Mr. Walker himself seems to have 
been conscious, since he places the genus Micropeza at the head of the 
next sub-family, Loxocerides ; from which results at least a prima facie 
connection of this genus with Calohata , to which, in fact, notwithstanding 
many differences, it stands in a nearer relation than to any other genus we 
can name. The enumeration of genera under the particular sub-families is, 
however, too incomplete to give a clear insight into the principle of Mr. 
Walker’s arrangement, and thus to afford the grounds for a deliberate judg¬ 
ment of it. 
17. Oestrid,e.—S o briefly characterized that we have to rely chiefly on 
the figures to supply the deficiency. 
After the Brachycera come the Hypocera , containing the single family 
PiiomDiE. The character of this family should have included the peculiar 
form of the metathorax, which forcibly recalls to mind the similar structure 
in the Dolichopidce. The large round joint of the antennae is called the 
third ; in this the author may, perhaps, be right, although we must confess 
that we have never been able to distinguish more than one very minute 
