The rate of discovery of birds new to Michigan should decrease over the years since the number of possible species is limited. However, the rate depends in part on the number of competent observers afield. So far, at least, the increase in field activity has overbalanced the depletion of potential new candidates for the Michigan list. On the essentially irrefutable evidence of a specimen or photograph, 18 species of birds have been added to the Michigan list in the mere six years since publication of "A Distributional Check-list of the Birds of Michigan," by Zimmerman and Van Tyne. Two more species have occurred that may be escapees from captivity.