212 r iiiri rsili/ of Califoniia I'liblicnfions in Zoolof/i/. | Vol 



Comparative Measurements of Woodchuck Mandibles.* 



For method of taking measurements, see Introduction. 

 All dimensions are in millimeters. 



Marmota 

 flarirenlpr{ ? ) 



from the Marmota flaviventer from 



Pine Forest Mts., Colorado 



Humboldt Co., . ^ -. 



Nevada. No. 7051 No. 7050 

 No, 7890 5 ^^- $ J^'- Average 

 Most anterior point of mandible 

 to most posterior point of an- 

 gular process 53.7 60.2 50.7 55.45 



Perpendicular distance to highest 

 jioint on articular process 

 (mandible resting horizontally 

 on a flat surface) 24.0 28.0 21.7 24.85 



Distance from dorso-posterior an- 

 gle of angular process to ven- 

 tro-posterior angle of articular 

 process 13.4 15.3 11.7 13.50 



Height of jaw perpendicularly, 

 measured at middle of pre- 

 molar 12.1 14.0 9.9 11.95 



Diastema — distance from poster- 

 ior margin of alveolus of in- 

 cisor to anterior margin of 

 alveolus of premolar 10.4 12.5 11.0 11.75 



Posterior margin of alveolus of 

 last molar to most posterior 

 point on angular process 23.6 27.3 19.3 23.30 



Length of cheek-tooth series — an- 

 terior margin of alveolus of 

 first cheek-tooth to posterior 

 margin of last..-- 18.0 19.1 18.6 18.85 



•■ This table shows the jaw from Nevada to be intermediate between 

 the two examples of faviventer from Colorado in all characters of size 

 considered except two, namely, diastema and length of cheel'-tooth series. 

 It is smaller than the juvenile faviventer in these respects. It will be 

 noted further that the measurements of no. 7890 are slightly less than 

 the average of the other two specimens in all characters except distance 

 from dorso-posterior angle of angular process to ventro-posterior angle of 

 articular process, and posterior margin of alveolus of last molar to most 

 posterior point on angular process. 



Large burrows, some of them evidently reeently used, were 

 observed on several parts of the higher slopes of the mountains. 

 I know of no other mammal than the woodchuck or badger, living 

 at the altitudes (around 9000 feet) at which these Imrrows were 

 observed, which could have made them. The possibility of tlie 

 ])resence of badgers at this height is remote. However, no wood- 

 chucks were heard or seen at any time, although several weeks 

 were spent in country which should have been inhabited by them. 



