THE AMERICAN MUSEUM JOURNAL 
differences produced in the horse by breeding or artificial selec- 
tion, Professor Osborn has enlisted the aid of Professor J. C. 
Ewart, who is well known for his experiments at Penicuik, Scot- 
land, in the interbreeding of horses and zebras. From Professor 
Ewart the Museum has secured a perfect Shetland pony, only 
314 inches high, the smallest on record. The first of the series 
of horse skulls showing the development of the teeth will soon 
be placed on exhibition. 
Six water-color paintings of horses, asses and zebras have 
been completed by Mr. Charles R. Knight, and put on view. 
This series has been made partly as a color-study for use in pre- 
paring the restorations of the extinct horses. 
The type specimens of the species of horses described by Dr. 
Joseph Leidy have been loaned to the Museum by the United 
States National Museum and the Philadelphia Academy of Sci- 
ences, for purposes of comparative study. 
The exhibit of Titanotheres in the northwest corner of the 
Hall of Fossil Vertebrates has been entirely rearranged to accord 
with the results of the studies which Professor Osborn has been 
making during the past winter for the United States Geological 
Survey. Small models of the heads of the four principal types 
of Titanotheres and of the ancestral form and a model of the 
running Brontotherium have been prepared by Mr. Knight, and 
are to be placed on exhibition near the fossil bones. 
ciate Curator of the Department of Mammalogy 
and Ornithology, is spending his vacation in mak- 
ing a cruise among the Bahama Islands, on a 
schooner chartered for the purpose, and is making collections of 
the birds and carrying on special studies of their habits. 
THE course of Saturday afternoon talks and laboratory exer- 
cises in ornithology, given in the auditorium of the Museum . 
during April and May, has proved to be popular, and is consid- 
ered very instructive and helpful by the large number of teach- 
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