162 
JOURNAL OF MAMMALOGY 
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Washington, vol. 19, p. 96. 
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Cambridge, Massachusetts. 
THE VALIDITY OF THE PENOBSCOT FIELD MOUSE 
By Leland C. Wyman 
In December, 1901, Mr. Reginald Heber Howe, Jr., described a new 
subspecies of Microtus pennsylvanicus which he had collected on Tumble 
Down Dick Island in Penobscot Bay, Maine, naming it Microtus 
pennsylvanicus shatiucki.^ There has been some doubt among mammal- 
ogists as to whether or not this form really differs from the ordinary 
meadow mouse of the mainland. Following are the results of a care- 
ful comparison of the type specimen and other skins of M. p. shattucki 
with about two-hundred skins of Microtus pennsylvanicus (Ord) in 
the collections of the Lee Museum of Bowdoin College, the Museum 
of Comparative Zoology of Harvard University, and various private 
collections. The specimens of M. p. shattucki which were examined 
consisted of the type and seven others of the original series from Tumble 
Down Dick and Ilesboro, Maine, now in the museum at Harvard and 
in the collection of the Boston Society of Natural History. These are 
the only specimens from the type locality which could be located. 
Others may exist in private collections. The specimens of Microtus 
pennsylvanicus used in the comparison were collected from four locali- 
ties in Maine; three islands of the Maine coast; Grand Manan Island, 
New Brunswick; one other locality in Canada; three localities in New 
Hampshire; eleven localities in Massachussetts ; seven islands near 
Cape Cod, Massachusetts; two localities in Rhode Island; one locality 
1 A New Race of Microtus pennsylvanicus. Reginald Heber Howe, Jr. Proc. 
Portland Soc. Nat. Hist., vol. 2, part 6, p. 201. Portland, Maine, December 31, 
1901. 
