Howell (op. cit.:16) referred a specimen from Cassopolis, Michigan, a locality that might be presumed to fall within the range of the more recently named S. c. saturatus, to S. c. stonei. Bole and Moulthrop did not mention this specimen when they described and named S. c. saturatus (1942). Neither did Burt, but Cassopolis is within the geographic range ascribed to S. c. cooperi on his map (The Mammals of Michigan, Univ. Michigan Press, p. 213, 1946). Examination (by Kelson and Hall) of the specimen (41777 MCZ) reveals that it resembles S. c. cooperi in shortness of hind foot (18 mm.), shortness of tail (18 mm.), narrowness across zygomata (16 mm.), and grayish pelage. In the long braincase, heavy rostrum, greater condylobasilar length, greater lambdoidal breadth, long rostrum, and longer incisive foramina, it agrees closely with specimens of S. c. saturatus, to which subspecies we refer the specimen.
Necker and Hatfield (Bull. Chicago Acad. Sci., 6:54, 1941) referred specimens from Rosiclaire, Illinois, to S. c. gossii. These specimens were not mentioned by Bole and Moulthrop (op. cit.) when they named S. c. saturatus although the specimens presumably would be referred to the newly-named subspecies. We have examined the pertinent specimens (Nos. 15781-15786 and 16049-16054 CNHM) and find that on the basis of dark color, long and slender skull, heavy incisors, and small cheek-teeth, they are referable to S. c. saturatus Bole and Moulthrop. None, however, has a tail so short as the type of S. c. saturatus. For that matter, the average length of the tail of six near topotypes (5 mi. W, 2½ mi. S Monticello, Piatt County, Illinois, Nos. 32037-32042 KU) exceeds that of the type (17.4 mm., range 12-20, as compared to 14 mm. for the type).
Synaptomys cooperi gossii (Coues)
1877. Arvicola (Synaptomys) gossii Coues, Monogr. N. Amer. Rodentia, p. 235 (published as a synonym of Synaptomys cooperi, but name stated to apply to Kansan specimens of which description and measurements are on p. 236), type from Neosho Falls, Woodson County, Kansas.
1897. Synaptomys cooperi gossii, Rhoads, Proc. Acad. Nat. Sci. Philadelphia, 49:307, June.
In view of the taxonomic treatment accorded by Bole and Moulthrop (Sci. Publs. Cleveland Mus. Nat. Hist, 5:149-151, September 11, 1942) to the lemming mice of the species Synaptomys cooperi, as explained in the preceding account, it has seemed desirable to examine Iowan specimens of this species. Hall and Kelson examined the necessary material and made the following conclusions. An adult male from Hillsboro (168453 USBS) has the lighter color and large skull of S. c. gossii to which Howell (N. Amer. Fauna, 50:19, August 5, 1927) referred the specimen. The more western specimen from Knoxville, a young male (190358 USNM), is almost exactly the same age as a male of S. c. saturatus from Bascom, Indiana (143701 USNM), and is but slightly older than a male S. c. gossii from Ft. Leavenworth, Kansas (91583 USBS). The upper molariform tooth-row is the same length in the specimens from Kansas and Iowa, but is longer in that from Indiana. The fact that the specimen from Knoxville closely resembles the Kansan specimen in other dimensions of the skull, which is larger than in the specimen from Indiana, gives a basis for applying the name Synaptomys cooperi gossii to the specimen from Knoxville. This is the same name recently used by Fichter and Hansen (Bull. Univ. Nebraska State Mus., 3(2):2, September, 1947) for the Iowan specimens, although they seemingly applied the name without being aware of Bole and Moulthrop's earlier naming of S. c. saturatus (Sci. Publs. Cleveland Mus. Nat. Hist., 5:149, September 11, 1942).
Synaptomys borealis sphagnicola Preble
1899. Synaptomys (Mictomys) sphagnicola Preble, Proc. Biol. Soc. Washington, 13:43, May 29, type from Fabyans, Coos County, New Hampshire.
1927. Synaptomys borealis sphagnicola, A. B. Howell, N. Amer. Fauna, 50:30, August 5.
Howell (N. Amer. Fauna, 50:30-31, August 5, 1927) had only eight specimens of this subspecies available when he revised the genus Synaptomys. Of these eight (Maine: Mount Katahdin, 2; New Brunswick: Near Bathurst, 1; New Hampshire: Fabyans, 1, the type; Quebec: St. Rose, 4), only the type and one of the specimens from St. Rose are adults. Concerning the others, Howell wrote (op. cit.:31): "The example from near Bathurst is not adult and has a damaged skull, so is identified provisionally. All other specimens are too young for positive diagnosis."