23 TRANSACTIONS OF THE [JUNE 4, 
At its conclusion the Academy adjourned. 
Wm. HALtock, 
Secretary of Section. 
J. F. Kemp, 
Recording Secretary. 
REGULAR BustINness MEETING. 
June 4th, 1894. 
The Academy met with Vice President Whitfield in the chair. 
Eleven persons present. The minutes of the last meeting were 
read and approved. 
The Secretary presented the following nominations from the 
Council: 
Prof. A. M. Mayer. 
Dr. Timothy Cheeseman. 
Mr. Henry E. Crampton. 
All of whom were elected. 
The Secretary read by title the following papers: 
A DIVISION OF THE EUTHERIAN MAMMALS INTO 
THE MESOPLACENTALIA AND 
CENOPLACENTALIA. 
By Henry FAIRFIELD OSBORN. 
In a recent address I endeavored to develop the idea that we 
should consider the Placentals as having exhibited two great. 
centres of functual radiation which were successive and largely 
independent of each other. The first of these was the group 
mainly discovered by Cope in the Puerco and now proved to 
extend back into the Cretaceous; the second is the group the 
earliest members of which were seen in the Puerco and which 
developed and radiated in the succeeding Tertiary. To these 
two groups the names Mesoplacentalia or Placentals distinctive 
of the Mesozoic period, and Cenoplacentalia or distinctively 
Tertiary Placentals, may be applied. 
