80 MEMOIRS OF THE CARNEGIE MUSEUM 
nearly like what is seen in Dinohyus. The posterior portion of this tooth in the 
latter genus is not unlike that of the European form, and shows a more advanced 
development than in Archxotherium. Altogether in Archxotheriwm the crowns of the 
molars are somewhat lower, the apices of the different points of the grinding surface 
are less united, and the teeth as a whole are less modified than in Hntelodon 
magnum and Dinohyus hollandi. 
MEASUREMENTS. 
Mm 
Length of alveolar border of maxillary and premaxillary..................066055 465 
DStan Ce OMe me ci In CIsOl tO) Wie rssh is de. csseep sateeeheciw GacwstersanceenseSedene 330 
Length of molar series............. 
Antero-posterior diameter of I2. 
Transverse ie es es 
“ & Trias 
Antero-posterior Ce posters eviay ih tienen Catach sie 8d OSE RRR A A ORY pee eon 
“3 Ks TEM GATINEAU DASE Fra etecdMeseces Pico atlases cateesiee’ 50 
Transverse ee ic OR Ce aA Cate om enn o FDO) 
Antero-posterior “ “ 39 
Transverse ee it 22 
Antero-posterior mt ce 38 
Transverse be be 22 
Antero-posterior & ct 42 
Transverse CG Gh 33 
Antero-posterior ee bt 37 
Transverse a Gb 40 
Antero-posterior 6 “ 42 
Transverse we Ie 44 
Antero-posterior he A 45 
Transverse “ BG 48 
Antero-posterior Ce ae 45 
Transverse oe We 47 
Tue Inrertor DeEntirion. 
(Plate LVIIL.) 
The incisors are much worn, but their outlines present more obtusely pointed 
crowns than in the older forms and the median pair is proportionately smaller, so 
that the gradual enlargement from I; to Ig is in about the same proportion as in 
the superior series. The teeth are crowded and occupy a more nearly transverse 
position in the front of the jaws than is seen in the Oligocene forms generally. The 
crown of Iz is much worn; and its antero-posterior exceeds its transverse diameter, 
so that it is oval in cross-section. I, is about twice the size of the median incisor 
and is also oval in cross-section, its antero-posterior being greater than its transverse 
