@ 1@ ) 
of smell, touch and hearing. It is evident they play a most 
important part in the intercourse of the sexes, for we inva- 
riably find them most strongly developed in the male. 
Observation teaches us that among the ants they commu- 
nicate intelligence ;—experiments confirm their service as 
organs of touch and hearing :—what a complex sense this 
combination produces!—but I fear their true function will 
be for ever concealed from us, for it is doubtlessly one to 
which it is proved by the organ that we do not possess any 
analogue. Their importance in the economy, particularly 
of the Hymenoptera, is distinctly proved by the complex 
apparatus provided for keeping them clean, and placed in 
the anterior leg, of which I shall speak in detail below. 
The Face is generally flat, sometimes slightly convex (the 
Mutillide, Sapyga), or sulcated (Crabro). The cyprus, 
although never articulated, is sometimes distinctly separated 
by suture, but very generally by a mere impression, which 
also is frequently obsolete. It undergoes a great variety 
of form, but is most generally transverse; frequently emar- 
ginate in front, the apices of which are sometimes pro- 
duced into tubercles (Oxybelus, Diodontus, some Cerceris,) in 
the latter it is laterally lobate, and has very frequently a 
longitudinal carina in the centre, which in Oxybelus is pro- 
duced in an aquiline form. In the majority of males, and 
in the female Crabros, it, as well as the face, is covered 
with a dense silvery or golden pubescence. 
I have nowarrived at the true oral organs, the investigation 
whereof Fabricius considered as essentially necessary to the 
determination of genera, in which he has been much too 
servilely followed by several eminent men. In the Fossorial 
group of the aculeate Hymenoptera, experience and Jurine 
have proved that their examination is of minor importance. 
I have consequently made no constant use of them in my 
