EXTERNAL ANATOMY OF INSECTS. 505 
Micropeplus and Anthophagus*. Upon examining the 
former genus, I find, that although Omalium planum and 
affinities, O. striatulum, and some others, appear not to 
have them, yet with the aid of a good magnifier they may 
be discovered in most species of that genus; as likewise 
in Eveesthetus. I find them also very conspicuous in 
A. Caraboides and other Anthophagi, but some species 
appear to want them. In these insects they are two in 
number, situated in the vertex a little behind the eyes 
but within them, and either at each end of a transverse 
furrow, or at the posterior termination of two longitu- 
dinal ones. Nor are they found in all the genera of the 
other Orders. In the Orthoptera, the Blattina, unless 
a white smooth spot on the inner and upper side of the 
eyes may be regarded as representing them, have them 
not; but in all the other genera of that Order they are 
to be found’. In the Hemiptera all the frog-hoppers 
(Stridulanies Latr.) are gifted with them; as are likewise 
Scutellera, Pentatoma, with many other Geocorise, and 
the Reduviade very remarkably; but many others in 
both sections of this Order, as Thrips, Coccus, Aphis, 
Capsus, Miris, Naucoris, Nepa, and Notonecta, &c. are 
deprived of them’. Of the Newroptera the Libellulina 
add séemmata to their large eyes, in the anterior angle 
* Magas. der Entomolog. iv. 410. 
> Latreille speaks of Phasma as having no stemmata; but it should 
seem that he examined only the apterous ones, all the winged indi- 
viduals, at least so far as I have examined them, having three very 
visible ones. It may, I think, be laid down as a rule, that the larvae 
and pupae of Orthoptera have not these organs. Probably their use 
is principally in flying ? 
° Flata phalenoides and affinities have no stemmata, while 
Flata reticulata and affinities have them: a proof that these tribes 
form distinct genera. 
