0. C. Marsh—New Tertiary Mammals. 223 
ridge. It indicates, moreover, an animal several times the bulk 
“4 that species. Probably other remains of both species were 
ound by our party, but have not been recognized as pertaining 
to this genus, 
Me : 
Antero-posterior diameter of last lower premolar,......... Ese 
Brees. Giamter, iis aus Socag st ese ay cd 5'8 
Ae t of anterior cusp above jaw,.......sse0. seseeecs .5°2 
eight of exterior cusp above jaW,........seesseeeereess 8 
This rare specimen was found, by Mr. O. Harger, in the shale 
near Henry’s Fork. The geological horizon was essentially the 
Same as at Grizzly Buttes. 
Triacodon nanus, sp. Nov. 
much smaller species, apparently not more than one-half 
the bulk of 7 Jallax, is indicated, likewise, by the peculiar last 
°wer premolar. This tooth, like that in the other species, has 
two fangs, There is a faint basal ridge, and the three pointed 
cusps, that give the crown its character, are more nearly of 
equal size than in either of the larger species. 
Measurements. 
antero-posterior diameter of last lower premolar,......... iene 
Peet eree CUM Gt oe is ie vas pegs ee aes 3° 
Height of anterior cusp above jaw,.....- bins ewan tess 2°5 
Height of exterior CUSP ADOVE JAW,.... ccs erenrertecercn 4: 
nna specimen, the only remains of the species at present 
i" Own, was discovered at Grizzly Buttes, in September last, by 
". G. G. Lobdell, Jr. 
Euryacodon lepidus, gen. et sp. nov. 
a tragment of an ane jaw containing the last two molars in 
‘ : ur collections contain other characteris- 
le fossils which 2 Re to be specifically identical with this 
the name, Paleacodon verus, but each has its inner m 
ae into a small tubercle. In the penultimate upper molar, 
'S tubercle is especially prominent. outer , also, 
Measurements. 
Space occupied by last two upper molars,...-------+++++ 4°3 mm- 
Antero-poste ior diameter of penultimate upper molar,....2°4 
Transverse GiAMeter, .. <6 sb sc see cose ak ees Canes nee 3°8 
Transverse diameter of last upper MOlar,. +++ sevsssess asso 
