Olson, R.E. 1980. The herpetofauna of Minnesota: II. Rare and restricted amphibians. Report submitted to the Minnesota Department of Natural Resources. Unpaged.
A question of paucity of or restricted nature of range regarding a particular amphibian species in Minnesota must evoke a response which is, each in its part, attached to specifics as to uncertainties. Observations during the nearly four decades following the appearance of Breckenridge's (1944) data on the herpetofauna of Minnesota, although a few published records exist from them, indicate the necessity of more in-depth and current work.
It has been the task of this project to set about to investigate this matter. With that in mind, the writer has begun the effort to 1) clarify the records as they presently exist, 2) substantiate questionable reports, 3) define ranges of particular species within the state, and 4) determine whether some peripheral species occur here at all. Hopefully some substantial ground has been gained in this regard.
Inasmuch as this report is preliminary, and a part of a more comprehensive investigation of the entire herpetofauna of the state, references to such items as literature and various museum collections are only cursory.