370 NATURAL SCIENCE [December 
most cheering to see the attention now being paid to scientific and 
technical education and to intellectual culture in the great commercial 
city of Liverpool. 
THE REDUCTION OF THE TEETH AMONG MAMMALS 
THE professors and lecturers in our Agricultural and Veterinary 
Colleges have many opportunities of making substantial contribu- 
tions to biology. They deal with a series of problems which the 
student of organisms uninfluenced by artificial surroundings can 
rarely hope to find within his range. They observe changes in the 
structure and function of organs which they are able to correlate 
with known factors in the process of domestication or cultivation of 
the animals or plants they happen to study. They also have 
facilities for embryological research among the vertebrates, far ex- 
ceeding those obtainable under any other circumstances. We who 
are interested in the purely theoretical questions of biology thus 
welcome with peculiar gratification any contribution from a naturalist 
who has taken full advantage of these favourable conditions, and 
enlivened the dull routine of teaching with comparatively broad 
generalisations. 
One such contribution is contained in the seventy-ninth annual 
Programm of the Royal Wurtemberg Agricultural Academy at 
Hohenheim, dated 1897, but received from the author, Professor 
W. Branco, a few weeks ago. Professor Branco is the distinguished 
palaeontologist who succeeded Quenstedt in the University of 
Tiibingen, but was unfortunately compelled by ill-health to relin- 
quish the duties of the professorship after too brief service. Having 
now happily recovered, he devotes his energies to the Academy of 
Hohenheim, and his unusually wide sympathies in biology still 
stand him in good stead. A short time ago he published a descrip- 
tion of some peculiar teeth, almost human in shape, from the Upper 
Eocene or Lower Miocene ‘ Bohnerz’ of Wurtemberg (Jahresh. 
Vereins fir vaterl. Naturk. Wirttemb., 1898, pp. 1-140, pls. i.-ii1.). 
He now follows this memoir by the present contribution, which 
discusses the nature and origin of the reduction of the dentition 
among mammals in general. 
After some preliminary considerations and a broad outline of 
the facts, Prof. Branco applies the knowledge he has obtained in the 
course of his professorial duties. He points out that one principal 
cause of the reduction of the teeth is the shortening of the jaws. 
Among domesticated animals this shortening is shown to be due to 
at least two causes. It happens when the food requires compara- 
tively little mastication ; animals of any particular race fed upon 
soft food produce short-faced descendants, while others of the same 
race continually fed upon hard food always retain longer jaws and 
