1947] 
Early Insect Life 
75 
by muscular movement to make this mechanism practical. 
At any rate, the adult Protodonata and Odonata are so 
much alike, I find it difficult to believe that their nymphs 
were very different. 
The insects which we have been considering so far are 
primitive types which we would expect to find as part of 
early insect life. The group we are now to discuss is not 
in this category. For although their wings were of the 
paheopterous type, the head was modified into a long 
rostrum, with suctorial mouth-parts. The best preserved 
specimen ( Eugereon ) of this group has been found in 
Upper Permian rocks of Germany, but other representa- 
tives, also with elongate beaks, have been collected in 
Carboniferous strata of France, Belgium, and England. 
Since these insects were at first thought to have been 
related to the Hemiptera, Handlirscli termed the order 
the Protoliemiptera. The choice of name was unfortu- 
nate, for, with the discovery of new specimens, it has 
become increasingly clear that they had nothing to do 
with the Hemiptera, but are instead closely related to the 
Palaeodictyoptera. The order was obviously a widely dis- 
tributed one, members having been found in Permo-Car- 
boniferous strata of both Europe and North America; 
and specimens from Trias sic rocks of Australia show that 
it persisted into the Mesozoic. The Triassic representa- 
tives, by the way, are remarkable in that the fore wings 
had a very large stridulatory area. The Palaeozoic Proto- 
hemiptera had long cerci and well developed prothoracic 
wing lobes, like those of the Palaeodictyoptera. The pres- 
ence of suctorial mouth-parts raises the question of feed- 
ing habits. It is obvious from their modified mouth-parts 
that the Protoliemiptera consumed liquid foods ; whether 
this was plant juice, from such gymnosperms as lycopods, 
seed-ferns, and horse-tails, or the blood of reptiles and 
amphibians, is uncertain. But it is most interesting that 
as far back as the Upper Carboniferous, at least two hun- 
dred twenty-five million years ago, the suctorial mecha- 
nism had been developed in insects ; and also that this 
device originated in relatives of the may-flies and dragon- 
flies, quite independent of its subsequent development in 
the Hemiptera and the Diptera. 
