654 
THE STUDY OF INSECTS . 
Family Nyssonid^: (Nys-son'i-dae). 
The Nyssonids {Nys-so'nids). 
These digger-wasps are of medium size. Some of them 
are remarkable for their close resemblance in form and mark¬ 
ings to true wasps of the family Eumenidae ; but they do not 
plait their wings like the true wasps. Little is recorded re¬ 
garding their habits; some species provision their nests with 
nymphs of leaf-hoppers, others with spittle-insects (Homop- 
tera). It is said that the species of the typical genus Nysson 
(Nys son) have the habit of feigning death and dropping to 
the ground when alarmed. 
We have about fifty species of this family in our fauna. 
Family Pi 11 LA nth I DM (PhiJan'thi-dae). 
The Philanthids {Phi-la n't bids). 
These digger-wasps are easily recognized by the charac¬ 
ters given in the table above. Figure 779 represents the wing 
of Cerceris (Cer-ce'ris) and shows the typical venation. The 
males are peculiar in having a fringe of hairs resembling a 
mustache on the free edge of the clypeus on each side. 
The Philanthids burrow in the earth. Some provision 
their nests with bees; others with beetles. The family con- 
tains about seventy-five North American species. 
