316 
ZOOLOGICAL LITEKATUKD, 
particularly distinct in the intermediate legs. The second ring 
is wanting in the Bees, and in various genera of Fossoria, but 
present in several Vespidse. The distinction founded on the 
single or double trochanter holds good as far as the hind legs 
are concerned. 
The species of Nysson described by Gerstacker are treated of 
by him in geographical groups^ commencing with the European 
species^ 11 in number. Asia and Australia furnish each a single 
species ; of the remainder^ 8 are American, 1 African, and 1 of 
unknown origin. 
Oxijhelus. Gerstacker (Zeitschr. ges. Naturw. xxx.) discusses 
the early history of this genus, which he characterizes at enor- 
mous length, the description of its generic peculiarities occu- 
pying no fewer than 29 pages. It is to be remarked, however, 
that this description includes many remarks comparing the 
structure of the difierent parts in this and other forms of Acu- 
leate Hymenoptera. With reference to the inequality of the 
facets in the eyes of Oxybelus (the central facets are larger than 
those of the periphery) Gerstacker takes occasion to notice the 
occurrence of a similar character in insects of other orders (/. c. 
pp. 10-15). Gerstacker discusses the alliances of Oxybelus {1. c. 
pp. 40-46), and thinks that it should be placed, at least provi- 
sionally, in a group by itself, which would most closely approach 
the thin-petiolated CrabronideSj such as Blephai'ipus j Thyreopus 
and Rhopalum. Its true place would be between the Cercerides, 
ending with Falarus and the Crabronides, commencing with 
Ceratocolus. After referring to the difficulty of determining 
the species of this genus and discussing the characters by means 
of which they are to be distinguished (/. c, pp. 47-52), Gerstacker 
proceeds to the description of the species hitherto detected in 
the neighbourhood of Berlin, of which he recognizes 16, tabu- 
lated on pp. 53-55. These are afterwards fully described, with 
a detailed and dated synonymy ; and a few new species from 
other parts of Europe are described in notes. The species of 
the neighbourhood of Berlin are as follows : — 
O. lineatus (Fab.) =&<?//< (Oliv.), pp. 55-59 j O. (Jur.) = 
hellus and hellicosus (Dalilb.)=/«rca^«s (St. F.) pp. C2-G5; O. mucronatus 
(Fab.) (Curt.)=/eroa: (Shuck.), pp. 67-70 ; O. nigripcs (Oliv.) == 
trispinosus (Dahlb. &c. nec Fab.), pp. 71-75 j O. hipunctalm (01iv.) = ?i/^ro- 
ceneus (^\iuck.)=h(emorrhoidalis (Dahlb.) = (Schill.), pp. 77-80 j 
O. latro (Oliv.) $ + <5 armiger (Oliv.), pp. 80-84; O. uniglumis (Linn.) = 
trispinosa (Fsi}a.')=punctata (Fab.)=^nde«s (Fab.) = (Don.) = 
pygmeem (Oliv.), pp. 85-89 ; O. variegatus (Wesm.) = ? hamorrhoklalis (Oliv.), 
pp. 94, 95 ; and 8 new species. 
Pclopeus. Saussure (Reiso der Novara, Zool. Ilym. pp. 28-29) discusses 
the yellow-spotted American species of this genus, which ho reduces to 6 
(tabulated p. 29). The species are as follows, with their varieties or nascent 
species ” ; — 
