64 IOWA STUDIES IN NATURAL HISTORY 
Subfamily Cydnine 
Pangaeus bilineatus (Say) 
Amnestus spinifrons (Say) 
Amnestus pusillus Uhler 
Family Pentatomide 
Subfamily Graphosomatine 
Podops cinctipes (Say) 
Podops parvulus (Van D.) 
Subfamily Pentatomine 
Brochymena arborea (Say) 
Brochymena quadripustulata (Fabr.) 
Trichopepla semivittata (Say) 
Hymenarcys nervosa (Say) 
Menecles incertus (Say) 
Thyanta custator (Fabr.) 
Acrosternum hilare (Say) 
CONCLUSION 
In conclusion it may be of some interest from the standpoint 
of geographic distribution to compare the pentatomid fauna 
of the Douglas Lake region in Michigan with the pentatomid 
fauna of the Lake Okoboji region in northwestern Iowa, at 
which place I have also made a study of the group. 
Although the two regions are rather widely separated—Lake 
Okoboji is about 500 miles west and 175 miles south of Douglas 
Lake—and the floral and geological conditions are somewhat 
different, both are lake regions. In addition, our collecting was 
undertaken for about the same length of time at each place and 
during the same season of the year, so that a reasonable basis 
for comparison is available. 
Perhaps a brief quotation from an earlier paper on the Lake 
Okoboji pentatomids* will suffice for a general explanation of 
conditions at that place. ‘‘The vicinity of the Macbride Lake- 
side Laboratory (on West Okoboji Lake) offers excellent col- 
lecting grounds all within easy access. Indeed, so many ecolo- 
gical areas are seldom found within so circumscribed a region. 
