Checkered White (Pieris protodice)
Checkered White (Pieris protodice)
Norman (Cleveland County), Oklahoma
30 June 2003 

Like the Dainty Sulphur and a few other butterflies for which I show photos from south of Illinois, the checkered white is more common in the south but often strays north to the Chicago area in late summer. 

Checkered White (Pieris protodice)
Nelson Lake Marsh, Kane County, Illinois
29 July 2001

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