626 THE INSECTS OF ANCIENT AMERICA. 
Europe, a few species have been found as low down as 
the Carboniferous rocks of Wetterau, Saarbrick, etc., 
but these fossils from the Upper Devonian carry the first 
appearance of insect-life back to a previous epoch, and 
make their advent in North America synchronous with 
that of land plants. 
The specimens obtained by Mr. Hartt are intrinsically 
interesting; although they are all fragments, broken gen- 
erally from the centre of the wing, enough distinctive 
parts remain to determine the character of the fossils. 
They are all Neuroptera, or Lace-winged flies, and, with 
the exception of one or two Ephemerina, or May-flies, 
represent families which are now extinct. One of them 
is provided with a few veins forming concentric rings near 
the base of the wing; these rings bear such a striking 
resemblance to the stridulating organ of the green grass- 
hoppers, that I am inclined to believe there were chirping 
Neuroptera in those days! 
_ Similar in interest are some specimens of Neuroptera 
from the Carboniferous beds of Morris, Illinois; they 
occurred in small flattened iron-stone concretions, like 
the clay-stones in clay banks of the present day. These 
Neuroptera also represent families distinct from any now 
living, and, like many of the Devonian insects, are syn- 
thetic in character; that is, combine in one and the same 
form features which, in after ages, are distributed among 
the members of different families. In this case the syn- 
thesis unites families belonging to different sections,— 
some to Neuroptera proper, alien to Pseudo-neuroptera. 
The Neuroptera proper include those families where the 
pupe are inactive, and the limbs are folded against the 
body; such as the Sialina, Hemerobina, Mantispade, 
“eps and Phryganina (Caddis-flies). In the Pseu- 
