514 bulletin: museum of comparative zoology. 



Diluvium of Elizabeth Hohle, Oberfranken, Germany, resemble the 

 Greenland Lemming — a Misothermus — in lacking the external 

 accessory lobe at the anterior end of the last lower molar, though 

 the internal lobe, characteristic of the subgenus, is present. Sanford 

 (1870) describes as Arvicola gulielmi the fossil lower jaw of a Dicro- 

 stonyx from England, in which the last molar (Sanford, 1870, pi. 8, 

 fig. 2b) seems to lack the small antero-internal enamel fold char- 

 acteristic of the subgenus Misothermus. The anterior outer fold, 

 however, is represented as strongly convex forward, so that it differs 

 from any of the known species and may not be accurately drawn. 

 A careful re-examination of all the fossil material available from 

 Europe is much desired to establish whether or not both subgenera 

 are represented there. 



The following American Collared Lemmings are recognized: — 

 DicROSTONYX HUDSONius (Pallas). 

 Labrador Collared Lemming. 



Mus hvdsonius Pallas, Nov. spec. Quad. Glir. ord., 1778, p. 208, pi. 26, fig. 



A, B, C. 

 Spalax hvdsonius Tiedemann, Zoologie, 1808, 1, p. 478. 

 Arvicola {Georychixs) hvdsoniiLS Cuvier, Regne anim., 1817, 1, p. 207. 

 Lemmus hvdsonius Desmarest, Mammalogie, 1820, p. 289. 

 Hipudaeus hvdsonius Lesson, Man. mammalogie, 1827, p. 277. 

 Hypijdaeus hvdsonius Fischer, Synopsis Mamm., 1829, p. 299 (misquotation). 

 Myodes hvdsonius Wagner, Schreber's saugethiere. Suppl., 1843, 3, p. 604. 

 Lemrnis (sic) hvdsonius Schinz, Synopsis Mamm., 1845, 2, p. 255. 

 Georychvs hvdsonius Audubon & Bachman, Quad. N. Amer., 1854, 3, p. 81 



(part) . 

 Myodes torquatus var. hvdsonius Major, Atti Soc. Ital. sci. nat. Milano, 1872, 



15, p. 122, pi., fig. 1, 2 (teeth). 

 Cuniculvs hvdsonius Coues, Proc. Acad. nat. sci. Phila., 1874, p. 196 (part). 

 Cuniculvs torquatus Coues, Monogr. N. Amer. Rodentia. Muridae, 1877, 



p. 246 (part). 

 Dicrostonyx torquatus Miller, N. Amer. fauna, 1896, no. 12, p. 38-40 (part), 



fig. 13 (teeth). 

 Dicrostonyx hvdsonivs Bangs, Proc. Biol. soc. Washington, 1897, 11, p. 237. 



Tyi^e. — Pallas based this species on sundry skins sent from Labra- 

 dor by the Moravian missionaries ("Fratrum evangelicorum") and 

 hence probably from the east coast. 



