IOWA PENTATOMOIDEA 
347 
NOTES ON IOWA PENTATOMOIDEA. 
DAYTON STONER. 
The average person usually refers to almost any kind of in- 
secf as a ^‘bug^^ but, employing the latter term in its proper 
sense, it represents the common name of an insect which belongs 
to one of the largest and best represented groups in North 
America. All bugs belong to the order Jlemiptera which name 
is derived from the character of the fore wings though wings 
are not present in all members of the order. The group may be 
briefly diagnosed as follows : 
Metamorphosis incomplete, i. e., there is no resting stage or 
period during which the insect does not take food in the course 
of its development after hatching. Mouth suctorial and of the 
same general form throughout all the stages ; owing to the struc- 
ture of the mouth parts these insects are able to take only 
liquid food. Wings developed outside the body except in a few 
apterous forms. Malpighian tubes few in number. Head set 
into pronotum. 
This large order, comprising about 6,000 species in North 
America, is of great variety and of considerable economic im- 
portance. The noted entomologist David Sharp says' that “If 
anything were to exterminate the enemies of Hemiptera, we 
ourselves should probably be starved in the. course of a few 
months.. ” 
The Hemiptera are apparently not closely related to any 
other existing order of insects and Kirkaldy suggests that, with- 
out doubt, they have sprung from a Paleozoic or Archeozoic 
neuropteroid source. As a matter of fact the Hemiptera have 
sprung from neuropteroid forms’ but no true Hemiptera existed 
in the Archeozoic and it is not until Lower Permian that the 
flrst hemipteroid type is found ; it is in that period that we find 
the first instances of typical hemipterous mouth, parts. 
The Hemiptera of Linneaus’ time were practically the Hem- 
iptera of the present day except that the family Thripidae is now 
excluded. Some authors have employed the term Khynchota or 
Rhyngota to designate the order but this seems to have sprung 
from Pabricius’ use of the name in his “Systema Entomologias ” 
