O. C. Marsh—New Tertiary Mammals, 213 
Antero-posterior diameter of last lower molar,........-. ica 
memcaveres diameter, i.» » 46 + a x +i+ae-bo5,0 4 ¢eacme eels 2°4 
Depth of jaw below last lower molar,....---++++++++++: 6°3 
The type specimen of this species was discovered, last autumn, 
near Henry’s Fork, Wyoming, by Mr. G. G. Lobdell, Jr. 
Other specimens were found in the same region by Mr. O. 
oe, Mr. J. J. DuBois, and Mr. T. G. Peck, of the Yale 
party, 
Hemiacodon nanus, sp. Dov. 
Measurements. 
Longitudinal extent of last four lower teeth,....+-+-+ +++: Bg accu 
Extent of three lower molars,.....-++-+-+ereeeete cree 9 
Antero-posterior diameter of last lower molar,.....-+---- 3.5 
FAMSVErse Giameter, ........-00csees coer eescsee seers : 
epth of jaw below first lower true molar,......-------+- 46 
aj The specimen on which the above description is based was 
Boovered by Mr. O. Harger, in September last, near Henry’s 
ork, Wyoming. 
_ Hemiacodon pucillus, sp. nov. 
A still smaller species, not larger than a mole, is indicated 
SY a fragment of a lower jaw containing the penultimate molar 
™ good condition. The jaw was proportionally more com- 
Measurements. 
qitero-posterior diameter of penultimate lower molar, ...2°3 ™™° 
H AnSverse diameter, ........e7ee-rttr erste aa ee ee ty 
Doett above jaw of anterior tubercles,...+++-+sss8+s8t* 17 
pth of jaw below this molar,....---++-++ssrtsreetctt 3°7 
: This specimen, the only known remains of the species, was 
ound in September, 1870, by Mr. H. B. Sargent, of the Yale 
Party. The locality was at Grizzly Buttes. 
