SCIENTIFIC SUMMARY. 
207- 
Mammalian remains differ from those of the Tort Bridger Eocene in the 
absence of species of the genus Palceosyops , and its replacement by Bath - 
motion (Cope), and by the presence of only one small Hyrachijus. Four new 
species of Toxodonts are among the discoveries reported ; they are referred to 
the new genera Ectoganus and Calamotion. The teeth of six or seven species 
of sharks and one Ostrea have been found with the Mammalian remains. 
The New Sub-Wealden boring is begun again. (The former one had failed' 
through the breaking of one of the borers.) The u Academy,” in one of its 
numbers for March, says : a A few weeks ago we referred to the action taken 
by the Sub-Wealden Exploration Committee in starting a new bore-hole at a 
short distance from the old site. Although it had been suggested that the 
second boring should be undertaken at some other locality, the Committee 
saw no reason for altering their original determination, and consequently the 
new hole was started on Feb. 11. The crown employed has a diameter of six 
inches, so that solid cores of nearly this size are now being extracted ; and 
these large rock cylinders, when studied, will no doubt yield valuable 
geological information on the characters of the Sub-Wealden rocks. 
New Order of Eocene Mammals . — At the last meeting of the Connecticut 
Academy, Eeb. 17, Professor 0. C. Marsh made a communication on a new 
order of Eocene Mammals, for which he proposed the name Tillodontia. 
These animals are among the most remarkable yet discovered in American 
strata, and seem to combine characters of several distinct groups, viz. : 
Carnivores, Ungulates, and Bodents. In Tillotherium (Marsh), the type of the 
order, the skull has the same general form as in the bears, but in its structure 
resembles that of Ungulates. The molar teeth are of the ungulate type, the 
canines are small, and in each jaw there is a pair of large scalpriform incisors 
faced with enamel, and growing from persistent pulps, as in Bodents. The 
2.1 8 
adult dentition is as follows : — Incisors, ^ ; canines, - • premolars, ~ 
molars, 
The articulation of the lower jaw with the skull corresponds to- 
that in Ungulates. The posterior nares open behind the last upper molars. 
The brain was small and somewhat convoluted. The skeleton most resembles 
that of Carnivores, especially the Ursitice , but the scaphoid and lunar bones 
are not united, and there is a third trochanter on the femur. The radius and 
ulna, and the tibia and fibula, are distinct. The feet are plantigrade, and 
each had five digits, all terminated with long, compressed and pointed 
ungual phalanges, somewhat similar to those in the bears. The other 
genera of this order are less known, but all apparently had the same general 
characters. There are two distinct families, Tillotheridcc, in which the 
large incisors grew from persistent pulps, while the molars have roots ; and 
the Stylinodontidce, in which all the teeth are rootless. Some of the animals, 
of this group were as large as a tapir. With Hyrax or the Toxodontia 
the present order appears to have no near affinities . — “ Silliman’s American 
Journal,” March 1875. 
