72 
Some Solitary Wasps op Texas. 
In getting the nest ready the only thing I have seen texense do is 
to plaster a few pellets of mud against the bottom of the tube. 
Thus the cap hole of the shot-gun shell was tightly closed with it. 
The length of the chambers depends on their calibre and varies 
from three-fourth inch to one and one-half inches. When a nest 
is composed of several cells in horizontal series, the partition is 
built from the bottom up and is therefore thickest at the bottom. 
In closing the last chamber an extra amount of mud is plastered 
on and the plug is brought flush with the surface. In about half 
the cases the final closure was made with two plugs from one-fourth 
to one-half inch apart leaving an empty space or false chamber be- 
tween them. This must certainly be an effective means of de- 
ceiving such parasitic enemies (should they have any) as lay their 
eggs by means of boring ovipositors into the nests of their aculeate 
hosts. 
T. texense has a way, as I have already pointed out above, 
in connection with Agenia subcorticalis , of economizing time in the 
matter of getting mortar for the nest. I had always thought that 
this was gotten from the moist banks of the creek or river, whither 
Pelopaeus pilgrimizes for her building material. But it is certain 
that many do not get mud from that source but instead take it 
from the nearest place obtainable, namely those great pyramids of 
the world of wasps, the abandoned mud-dauber’s nests just at hand. 
Soon after I had begun inducing texense to make her home with 
us and build her nests on the gallery of the Lucksinger country 
home, the old mud-dauber nests began to decrease perceptibly in 
size, their material being used again in similar architectural enter- 
prises. Trypoxylon flies from her nest to a suitable place on a 
mud-dauberis nests and begins to gnaw off a piece of the dirt with 
her mandibles moistening it with saliva as she works. Pelopaeus’ 
dd house is hard and one can hear the grating and clicking of 
Trypoxylon s mandibles upon it as well as the hum of her wings 
under the strain of her work. Finally a pellet as large as her head 
is loosened and the wasp, just as the pellet is ready to drop, catches 
it “under her chin,” as it were, and takes it to her nest. The dirt 
its moist when plastered on and one can see the moist spot from 
which a wad of it has just been taken. To this same spot the wasp 
returns for successive loads, thus economizing in the expenditure 
of saliva necessary to wet the dirt. This requires, of cburse, more 
moisture, even for a single partition, than the wasp’s body can well 
hold and it becomes necessary to replenish the stock at intervals. 
So I have noticed that after every four or five loads the wasp flies 
