FAMILY FORMICIDM. 
Subfamily Ponerirtce Mayr. 
Tribe Prionomyrmicini, trib. nov. 
Genus JPrionomyrmex Mayr. 
This very interesting genus was established by Mayr on a single 
imperfect worker in the Berendt Collection. Examination of eight 
specimens, some of which are in an excellent state of preservation, 
enables me to add the following details to his generic description: 
The clypeus is triangulär, projects forward and is acutely pointed in 
the middle; it is flattened or feebly concave and fills out the space 
between the bases of the long, ensiform, denticulate mandibles when 
they are closed. Maxillary palpi 6-jointed; labial palpi 4-jointed. 
Frontal carinse subparallel, their anterior ends somewhat lobe-like and 
flattened, but small and horizontal. Frontal area absent. Eyes large 
and convex and at the middle of the sides of the head, not behind 
the middle, as stated by Mayr. Ocelli often absent. Antennse 12-jointed, 
slender; funiculus filiform, without a club, all its joints decidedly 
longer than broad. All the tibise with pectinated spurs. Fourth tarsal 
joint deeply bilobed; claws stout, bidentate. 
This genus, as Mayr has shown, is related to the Australian 
Myrmecia, which Emery rightly regards as comprising the most gene- 
ralized of living ants. Prionomyrmex is even more primitive in its 
structure and therefore deserves to rank as the archetype of all known 
Formicidce, for when we compare it with Myrmecia , we find that its 
mandibles, though greatly elongated, are not linear and specialized, 
but have a distinct and uniformly denticulate masticatory border, the 
clypeus is well-developed and the pedicel of the abdomen and gaster 
are more primitive and more like those of the Ponerince in general 
than in the Australian genus, in which the structure of these parts 
recalls that of certain Myrmicince (Pseudomyrmini). 
