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he collection of the University of Kansas Museum of Natural History there is still another specimen. It is an adult male topotype (No. 6483 KU, formerly No. 72 in the collection of Alfred E. Preble) obtained on August 21, 1905, at Fabyans, New Hampshire. The measurements of this specimen are as follows (measurements in parenthesis are those of the type as given by Howell, _op. cit._): Total length, 135 (132); tail, 26 (24); hind foot, 22 (20); condylobasilar length, 25.1 (25.8); rostral length, 6.5 (6.8); rostral breadth, 4.7 (4.9); interorbital breadth, 3.3 (2.8); zygomatic breadth, 15.4 (16.0); lambdoidal breadth, 12.1 (12.4); incisive foramina, 5.9 (5.7); height of skull, 9.1 (9.3). Howell (_op. cit._:30) characterized _S. b. sphagnicola_ as: "Large and high [skull] with narrow interorbital sharply ridged, the ridges of the type being joined for a distance of 4 millimeters; interparietal narrow and rectangular. The rostrum is long, tapering very little, and the nasals, slightly constricted medially are quite narrow posteriorly. The incisive foramina are long and wide." Howell further stated (_op. cit._:30-31) that: "It is hard to predict what will be found to constitute the most valuable cranial characters in distinguishing this race from adult _medioximus_. The discernible differences now are in the shape of the interparietals, rostral characters, and interorbital differences that will probably not hold good when animals of the same age are compared." As can be seen from a comparison of the measurements given above for the type and the topotype, some of the characteristics given by Howell are not found in the topotype: The interorbital region is not narrow (in fact it is wider than it ordinarily is in some other subspecies of _Synaptomys borealis_) and the incisive foramina are not longer than in other subspecies of _Synaptomys borealis_. As far as present material permits us to judge, _Synaptomys borealis sphagnicola_ is characterized, cranially, by: Skull large; interorbital region sharply ridged (the ridges being joined for a distance of 4 mm. in the type and of 4.5 mm. in the topotype); rostrum long, tapering relatively little; nasals slightly constricted medially and unusually narrow posteriorly; interparietal narrow and rectangular. Clethrionomys occidentalis caurinus (Bailey) 1898. _Evotomys caurinus_ Bailey, Proc. Biol. Soc. Washington, 12:21, January 27, type from Lund, east shore Mal
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