1884] Geology and Paleontology. 6I 
present, small. The superior incisors are well developed and dis- 
play no tendency towards the rodent type. A portion of lower 
jaw adheres to the skull, and may belong to the same animal. It 
supports the last two molars. These have two anterior, opposite, 
approximated cusps. The heel of the penultimate molar is 
rather large, and has a raised edge, which develops two tubercles 
at the angles. 
L[ndrodcn malaris, sp. nov.— Char. Specif—The first and third 
superior incisors are a little larger than the second. Canine pre- 
ceded and followed by diastemata, each of which is 1.5 times as 
long as the long diameter of the base of the crown. Premolars 
separated from each other and from the first true molars by inter- 
spaces half as long as the diastemata. Neither tooth has any basal 
tubercles, but the posterior has a weak external cingulum, which is 
stronger posteriorly. The internal cusp of the same tooth is an- 
terior, and is acute and elevated. The superior true molars have a 
strong external cingulum, which rises into a small tubercle oppo- 
site the space between the external principal cusps. Of the latter 
the anterior is a little more conic than the posterior, and both are 
well within the external border. On the last molar the posterior 
external cusp is continuous with the external intermediate tuber- 
cle, and forms a cutting edge within the posterior margin of the 
crown, The posterior inner tubercle is rather large, and pro- 
jects further inwards than the apex of the anterior V or the sec- 
ond true molar, but not so far as in the species of Anisonchus 
and Haploconus. 
The surface of the cranium is too much obscured by cracks 
_ and films of matrix to permit a view of the sutures and foramina. 
The face is wide, as the posterior part of the maxillary and the 
malar bones are expanded outwards. I have not yet been able 
to ascertain the condition of the orbit posteriorly. The mandibu- 
Jar ramus is rather slender. 
MEASUREMENTS. M. 
Length of dental series from posterior base of I IIT.........--.05+ oo OIRR 
Length of hases of superior incisors Seek wees v (0000 
Length of premolars on maxillary bone ..... OT One 
RODE base of Pon. IY oo icons Aosa ieii rere .0028 
es a ee ty Ns casi cannes .0038 
Diameters M. 11 { anteroposterior... 2... esse scence ese eee tere ceereee + 0033 
t erse PE A E E R . -0040 
Diameters inferior M. I { aNteroposteriOr ..os+ts:»rssesoeežeresosennr «0032 
i SFBNGVOTSE . uss cecacessvues s con 0039 
Depth of ramus mandibuli at M. H ..... ORE nahy -0070 
interest, In the shortening of its dental series it is the most spe- 
Cialized genus of the epoch, while the forms of its true molars 
