Vol. 68.] LEMMING-EEMAINS PEOM THE ARCTIC BED. 249 



for the writer has foiiiid perfectly fresh and pleochroic andalusite in 

 the Eagshot Sands of Brentwood, the Woolwich and Reading Beds 

 of Plumstead and J^orthwood, the Thanet Sand of Crayford, the 

 Folkestone Sands (Lower Greensand) of Dunton Green, Limpsfield 

 and Reigate, and the AVealden Ironsands of Shotover Hill. That 

 andalusite has not previously been recorded from these beds is 

 probably due to its scarcity and to the difficulty of detecting it 

 when the grains do not show striking pleochroism, as also to the 

 small number of workers on the petrology of sedimentary rocks. 



Appendix YII. — T^ote on Lemming-Remains /rom the Aectic Bed at 

 Angel Road. By Maetin A. C. Hinton. 



I AM indebted to Mr, Warren for permission to study the small 

 bones which he has so carefully collected from the Arctic Bed at 

 Angel Road. The remains are exceptionally fragile, and they say 

 much for Mr. Warren's skill and perseverance. 



All the specimens are referable to the species of Dicrostonycc which 

 occurs in the deposit of the Ightham Fissures, namely, D. lienseli} 

 All the more important parts of the skeleton are more or less well 

 represented ; and, when fully worked out, the collection will form 

 a valuable contribution to our knowledge of this form. It com- 

 prises the remains of from eight to ten individuals, and includes seven 

 palatal specimens in six of which the maxillary teeth are present. 

 These teeth agree in form with those of D. henseli ; the anterior 

 and middle molars (dm.-L and m.-l) have the posterior walls of 

 their 4th inner and 3rd inner prisms respectively reduced, and 

 each tooth completely lacks all trace of the minute vestigial inner 

 angle which occurs behind the prisms named in D. torquatus and 

 D. gulielmi. The skulls, moreover, agree in size, in their narrow 

 nasals, small and peculiarly shaped bullae, palatal structure, etc., 

 with D. lienseli. 



D. lienseli is an extinct form known from the German Pleistocene, 

 the Ightham Fissures, Langwith Cave, and Doneraile Cave (County 

 Clare). Most of the living species of Dim^ostonyx live in the Arctic 

 tundra of the Old and New Worlds, and the form living in 

 Grinnell Land reaches 83° or 84° lat. N". On the other hand, we 

 must not forget, in drawing conclusions from the occurrence of 

 two species of Dicrostonyx in the late Pleistocene of temperate 

 Europe, that one living form still inhabits Unalaska (54° lat. I^., 

 D. unalascensis) and that our fossils represent extinct species. 



1 M. A. C. Hinton, Ann. & Mag. Nat. Hist. ser. 8, vol. vi (1910) p. 37 • 

 and Proc. Geol. Assoc. toI. xxi (1910-11) p. 496. 



