32 
REVIEWS. 
RECENT WORKS ON THE DIPTERA OF NORTHERN EUROPE. 
SUPPLEMENTARY NOTICE. 
Zetterstedt, Diptera Scandinavia. Tom. XII. 8vo. Lundse, 1855. 
Stenhammar, Copromyzina Scandinavia. 8vo. pp. 184,. Holmim, 
1855. 
In a previous number (July, 1855) we have reviewed at large Zetterstedt’s 
important work on the Diptera of Sweden, Norway, Denmark, Lapland, and 
Finland, completed in the year 1852, in the compass of eleven 8vo. vo- 
umes. The twelfth volume, which has appeared after the further lapse of 
three years, is simply a supplement, containing descriptions of the species 
added to the fauna of that region in the interval, and some further docu¬ 
ments upon the distribution and loGal range of those before enumerated. 
The species added amount to a hundred and seventy-eight, counting in a few 
recorded, during the intervening years, by Rohemann, Wahlberg, and Sten¬ 
hammar. Of this number, fifty-eight, or a third of the whole, are given as 
new species. The genus Idia is for the first time introduced into the 
Swedish fauna ; and with this Mochlonyx may be coupled, though inclu¬ 
ded in Corethra. Modifications of the system in the preceding volumes 
there are none, nor yet rectifications of the nomenclature, excepting in one 
or two instances of trivial names of repeated occurrence. In this respect 
there remains for his successors a task, declined by the veteran author, well 
worth the pains and time requisite for its due performance, since Zetterstedt 
henceforth takes place beside Meigen as a classic of the science. 
We have also to notice another volume which may serve for a specimen 
of the edifice we would desire to see erected on the foundation that Zetter¬ 
stedt has laid. The expectations that were raised by Stenhammar’s re¬ 
markable Monograph of the Swedish Ephydrinse have not been disappointed 
in his more recent essay on the Copromyzinse (Sphaerocerini), although the 
narrower groundwork has scarcely afforded as much room for originality. In 
both, the same insight into natural affinities, and the like minute compara¬ 
tive examination of all the parts, for the expressive marks of these, have 
succeeded in reducing the multitude of species, here largely increased by the 
diligence of the collector, into a very fair and graduated arrangement, illus¬ 
trated by descriptions as full as they could well be made without needless 
and tedious repetition, and adapted to the purposes of the student by the 
consistent use of a precise glossary, and by the constantly relative aspect in 
which they have been conceived. In the more recent essay, which we are 
now considering in particular, the synonymy of the generic and trivial 
names has been weighed in an impartial balance, and the right of priority 
recognised with an anxious fidelity in discussion which we cannot but attest, 
