HYMENOP TER A. 
657 
We have found the nests of Trypoxylon frigidurn (Try- 
pox'y-lon frig'i-dum) very common in branches of sumach 
(Fig. 785), more common perhaps than those of any other 
insect except the little carpenter-bee, Ceratina . The cells 
of the nest of Trypoxylon are separated by partitions of mud, 
and the pupa when full grown makes a very slender cocoon, 
with the upper end rounded and sometimes slightly swollen, 
and the lower end blunt and of denser texture than the 
remainder of the cocoon. The adult insect is very slender 
and lacks the yellow bands on the abdomen, possessed by 
most members of this family. 
Superfamily VESPINA (Ves-pi'na). 
The True Wasps. 
All members of this superfamily are winged, and when 
at rest fold their wings lengthwise like a fan. In this last 
respect they differ from all other Hymenoptera except a 
single genus of Chalcis-flies, Leucospis (Leu-cos'pis). The 
prothorax is prolonged backwards on each side to the 
base of the front wing ; the eyes are kidney-shaped ; and the 
legs are not formed for burrowing, being free from spines and 
bristles. 
Three families are included in this superfamily; these 
can be separated by the following table:— 
A. Antennas clavate or knobbed at tip. p. 657 .Masarid^e. 
AA. Antennas filiform or nearly so. 
B. Tibias of the middle legs with a single terminal spur; tarsal 
claws armed with a tooth, p. 658 .Eumenid^e. 
BB. Tibiae of the middle legs with two terminal spurs; tarsal 
claws simple, p. 660 .VespidjE. 
Family MASARIDJE (Ma-sar'i-dae). 
The Guest-wasps. 
This is a small family of which only seven species are 
known to occur in the United States. These are found in 
Texas and the far West. As yet nothing is known regarding 
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