_Rattus rattus rattus._ Black Rat.--Covert[6] states that the species is "very rare. I have but one specimen, which was caught at the Michigan Central R. R. Depot." [Footnote 6: Covert, A. B., in History of Washtenaw County, pp. 193-194, 1881.] _Mustela allegheniensis._ Least Weasel.--Covert says, "The only specimens of this mammal I have had were brought in this winter" (1881). I have not been able to find these specimens, which were doubtless small females of _Mustela noveboracensis_.