ALLEN: AMERICAN COLLARED LEMMINGS. 533 



Measvj^ements. — The type measured in the flesh as follows: — total 

 length 146 mm.; tail 17; hind foot 20. 



The skull of the type lacks the occipital portion; it measures: — tip 

 of nasals to posterior border of interparietal 28.5 mm.; nasals 9.1; 

 palatal length 18; diastema 10.2; zygomatic width 20; interorbital 

 width 4.5; upper molar row (alveoli) 8; lower molar row (alveoli) 7.9. 



Geographic distribution. — This insular species is confined to St. 

 Lawrence Island, where like the large Microtus innuitus, it seems to 

 have become differentiated through isolation. 



Remarks. — This is a very gray, bleached-appearing species com- 

 pared with the Alaskan rubricatus. But four specimens were taken 

 by Mr. DLxon during his brief stay at St. Lawrence Island. One 

 of these was a subadult female, containing four embryos, June 24th. 

 Two other specimens of about the same age agree with this last in 

 having a somewhat browner tint to the back than the type, an older 

 animal. Nelson, as long ago as 1887, recorded the lemming as com- 

 mon on this and the Bering Strait Islands. 



Specimens examined. — Four from St. Lawrence Island (M. C. Z.). 



DiCROSTONYX GROENLANDICUS (Traill). 



Greenland Collared Lemming. 



Mus groenlandicus Traill, Scoresby's Journ. voyage northern whale-fishery, 



1823, p. 416. 

 Lemmus hvdsonius Sabine, Parry's voyage. Suppl. to app., 1824, p. clxxxviii 



(- 188). 

 Lemnus (sic) groenlandicus Schinz, Synopsis Mamm., 1845, 2, p. 256. 

 Hyptidaeus groenlandicus Reinhardt, Rink's Gr^nl. geogr. stat. beskriv., 1857, 



p. 8. 

 Myodes torquatus var. gr<t>nlandicus Brown, Proc. Zool. soc. London, 1868, p. 



350. 

 Myodes groenlandicus Wagner, Schreber'^s Saugethiere. Suppl., 1843, 3, 



p. 606. 

 Myodes torquatus Feilden, Zoologist, 1877, ser. 3, 1, p. 320. 

 Cuniculus torquahis Greely, Three years of Arctic service, 1886, 2, p. 363 



(part) . 

 Dicrostony.v torquatus Miller, N. Araer. fauna, 1896, no. 12, p. 38-40 (part). 

 Dicrostonyx hudsoyiius Elliot, Field Columbian mus. publ. Zool. ser., 1901, 



2, p. 209 (not Mus hvdsonius Pallas, 1778). 

 Dicrostonyx hvdsonius groenlandicus Jacobi, Abh. u. ber. K. zool. anthrop.- 



ethnogr. mus. Dresden, 1911, 12, no. 4, p. 8. 



