372 Br. C. I. Forsyth Major — Some Rodents from Oeningen. 



These differences from Lagomys strengthen the opinion enounced 

 by Schlosser, that the Miocene fossil is to be considered as a separate 

 genus (Lagopsis), and at the same time they present a further 

 link in the gradual transformation of the tooth-pattern (Titanomys — 

 Prolagus — Lagopsis — Lagomys — Lepus), which begins in the hind- 

 most molar of Lagomyidae, and gradually proceeds forwards, stopping 

 at p. 1 in Lagopsis and Lagomys and at p. 2 in Lepus. This is not 

 the place to enter into the details of this interesting evolution, which 

 is exhaustively described elsewhere. 



I append the measurements of the teeth described and of some of 

 the bones of the same specimen, No. 42,815. 



mm. 



Length of the three upper premolars 5-o 



Breadth of p. 1 3-5 



,, p. 2 (posteriorly) 3-5 



,, p. 1 2-0 



Length of scapula ... ... ... ... ... ... 32"5 



,, humerus ... ... ... ... ... ... 36 



,, ulna ... ... ... ... ... ... 36 



,, femur ... ... ... ... .. ... 47 



We have, then, been able to demonstrate conclusively that Lagopsis 

 verus (Hens.) is a member of the fauna of Oeningen. It is not, 

 however, in the least certain that all the large-sized Lagomyidae 

 of the same deposit belong to this species, nor even to the genus 

 Lagopsis ; for my part I am looking for the discovery of Titanomys 

 Fontannesi (Dep.) amongst Oeningen fossils. If the Carlsruhe 

 specimen still exists, and is in the same condition in which it was 

 figured by H. v. Meyer, a careful developing would doubtless givo 

 good results and allow of an exact determination . 



3. Cricetodon minus, Lartet. 



The genus Cricetodon is now for the first time mentioned as 

 a member of the fauna of Oeningen. In previous lists of the 

 mammals from this locality, the latest of which is by Deperet,^ 

 the genus Miis is enumerated; this appears to me very doubtful, 

 the latter genus having never been met with in contemporaneous 

 deposits. 



In the Catalogue of Fossil Mammalia of the British Museum,* 

 two skeletons of Oeningen from the Breda Collection figure under 

 the heading ' Mus (?), sp.' In one of these. No. 42,823, of which slab 

 and counterpart are preserved, I have laid bare a molar tooth which 

 proves to be the anterior right lower molar of a Cricetodon, corre- 

 sponding in its size and in the character of a unicuspidate anterior 

 tubercle to Cricetodon minus, Lartet, from Sansan, La Grive-Saint- 

 Alban, Steinheim, etc. 



The specimen No. 42,822, also from Oeningen,^ is not a ' Lagomys,' 



1 Ch. Deperet, " Classif. etParall. du Systems Miocene" : Bull. Soc. Geol. France,. 

 3" serie, xxi, p. 245 (1893). 



2 I, p. 227. 



3 Cat. Foss. Mamm., i, p. 258. 



