103 
cuckoo wasps, bombyliid flies, ants and others follow her within 
and decimate her brood as they do outdoors. 
Pseudagenia okawa Rohwer. 
Length 9 mm.; gray-black. 








Fig. 50. Bamboo twig 
split open to show 
the three cells of 
Pseudagenia okawa. 
Natural size. 
* Nipa fructicans Wurmb. is a native palm common in 
leaves furnish ‘‘shingles’’ 
Unless we make use of a good magnifying 
glass in our field study of wasps, many spe- 
cies are not to be separated from others. 
This is particularly applicable to certain 
wasps that prey on Orthoptera (grasshop- 
pers, crickets, etc.) and to the large psam- 
mocharid genus Pseudagenia. Here, how- 
ever, their nesting habits often help us; the 
shape, number and arrangement of the Pseu- 
dagenia cells aid in differentiating the spe- 
cies. So, too, with the twig-nesting wasp 
P. okawa. She looks much like some others, 
but nests differently. I found her partition- 
ing off the hollows of slender twigs into from 
two to four cells and storing them with de- 
legged spiders, (Fig. 50). I found but 
three nests—all A twigs on the ground in 
the shade of a large mango tree. The inner 
cell plugs are of mud, and the outer one, 
which shuts off her nest from the outside 
world—moisture and ants—is in addition, 
smeared with a gummy substance. I reared 
four Pseudagenia okawa in June, 1917. 

Ageniella unifasciata (Ashm.) and Ageniella 
williamsi Rohwer 
Length about 7 mm.; fuscous spot on 
fore wing. 
These two little species, save for the pres- 
ence in A. unifasciata of a distinct median 
tooth on the margin of the clypeus, are very 
much alike. Both are abundant lowland in- 
sects. A. unifasciata may have as many as 
nine cells to a nest. The cells are com- 
monly arranged in rows on walls, tree trunks, 
etc., and provisioned with a delegged spider. 
The cells may be also built on twigs. 
tidewater lands, and 
for bamboo-frame houses and huts. 
