Tomatillas (tomatillos) Physalis ixocarpa Lam. (also P. philadelphica Lam.), Family;  Solanaceae.  Also, called husk tomato or ground cherries are members of the nightshade family as are tomatoes and peppers.  Tomatillas are used to make salsa verde. 

Ground cherry a similar plant, is found in the wild in the Eastern United States.

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Mexican Medicine:  Native Americans used the juice squeezed from the fruit as an eye wash.

SALSA VERDE:  Boil a dozen tomatillas with a half dozen hot peppers (JALAPENO).  Cook until tender.  set aside and let cool.  Then blend the peppers and tomatillas, add lime juice and use on meat dishes, or with chips.