224 
The Queensland Naturalist. 
VoL. I. 
an example of a “ captured ” tributary of one of the former 
western flowing streams. Mt. Edwards consists of trachyte,- 
and several specimens showing beautifully banded weather- 
ing w'ere obtained. 
We then proceeded tow^ards StenzeFs farm, and just 
before reaching it, we came upon a fine examnle of a 
mottled trachyte dyke with pitch stone on its edge. This 
was black in colour and spherulitic in structure. It was 
the first occasion daring our, trip that we had found pitch 
stone in situ, though we aftei wards found it again, this time 
of a dark green colour, near the Moogerah School. At 
StenzeFs farm we also met with a dyke of banded rhyolite 
intruding the Walloon conglomerates and grits. 
Tow^ards the end of our stay, we paid a visit to the 
bed of Reynolds Creek in order to add to our collection of 
specimens. The following rocks were obtained : — aplite,. 
grorudite, solvsbergite, amygdaloidal trachyte containing 
sodalite and phacolite, chalcedony, dacite, quartz diabase,, 
olivine basalt and some fine breccias. A large boulder 
showing the junction of aplite and andesite w'as also found. 
We travelled back to Engelsburg by a different route,, 
and on the road side, near Mt. French, specimens of comen- 
dite were procured. This rock is very similar to grorudite, 
but the free quartz present is only visible under the micro- 
scope. The Mt. French comendite has been analysed and 
has been found to be very acidic in composition. It con- 
tains about 72 per cent, of silica, whilst a normal trachyte 
contains only 62 per cent. 
The fact that our trip w^as so successful W'as entirely 
due to the unselfish and untiring labours of Mr. Wearne, 
who carefully planned the arrangements for each days’" 
w^ork. Through his efforts attention has been drawn to 
a district exceedingly interesting from a geological point 
of view', and one w'hich is well w'orthy of an extended visit 
by our Field Naturalist Club. 
THE NATURALIZATION OF AN EXOTIC ANT 
{PHEIDOLE MEGACEPHALA, Ftzb.) 
By Henry Tryon. 
The Ants exhibited, in such numbers, are examples 
of a species named Pheidole megucephala, (Fabr.). 
The name “ Pheidole” signifies economically laborious,, 
and w'as bestowed in 1841 on one of this group of ants by 
Wesow^ood (2) to commemorate the fact that it is most 
indefatigable in its special habit of storing garnered seeds. 
It will be remembered in this connection, that the 
exhibitor himself formerly described a Queensland Pheidole 
