Very interesting to ornithologists are the few heath hens, the eastern representative of the prairie hen (pinnated grouse), which are found on the island of Martha's Vineyard, and are the sole survivors in the eastern states of one of the finest of American game birds, now practically exterminated even on the western plains.
Prairie chickens (pinnated grouse), pheasants and wild turkeys, all very common as late as 1880, are no longer to be found save in remote and thinly-settled districts.
The game birds include quail (Bob White), ruffed grouse and a few pinnated grouse (once very plentiful, then nearly exterminated, but now apparently reappearing under strict protection), and such water birds as the mallard duck, wood duck, blueand green-winged teals, Wilson's snipe, and greater and lesser yellow legs (snipe).
The wild turkey, once abundant, was near extermination in 1886, and prairie chickens (pinnated grouse) have also greatly diminished in number.
In Polyurthra and Pteroessa they are numerous, pinnated (feathered), and are doubtless used for active swimming by jerks; they can be moved up or down by special muscles attached to their bases, which project into the body.