The Dictionary of Biochemistry is a pioneering effort in an entirely
new field. There have been no previous dictionaries of this kind. Further-
more, the concept of a "dictionary" has been changing from that of a
mere alphabetical glossary to something resembling an encyclopedia. At
least a dozen of conflicting possibilities of offerded themselves at the planning
of this volume, each of which was both enthusiastically supported and
violently attacked by people wih strong preferences and aversions. There
was only one thing left to do and that was to try to reconcile seeming
contradictions and to combine as many features as possible. All of this
had to be done within serious limitations of space and serious limitations
of cooperation due to the outbreak of the war. Consequently, this effort
breaks ground in many directions. The dictionary contains a great deal of
glossary material and also a great deal of fairly lengthy authoritative
discussion. It tries to maintain a balance between obsolescent, established
and newly explored material. It is designed for readers of biochemical
literature whio might want the definitions of term used more than a
decade ago as well as of terms just coined. There was no intention of
replacing text-books or abstract or review journals, except insofar as
certain items are greatly neglected or are not easily available. This will
account for what might appear as too liberal an allowance for articles on
teeth, hair, biochemistry of Phychiatry, phosphate bond energy, bac-
teriophage, etc., and a corresponding brevity on topics found in every
text. Articles, like Prof. Witzemann's unified discussion of carbohydrate
and fat metabolism, also represent an effort at something different, highly
synthetic in the midst of the atomism of a dictionary.

It is highly fitting that a scientific dictionary should itself be experi-
mental. In view of this we earnestly request suggestions from workers in
the field, be they experts or students, and from workers from neighboring
fields who might want to recieve or give information from their point of
view. Our criteria must change with growing experience in the actual
practical use of the dictionary.

We take this occasion to thank the collaborators, whose names are
listed separately; to acknowledge the fıne courtesy of Dr. R. E. Gruber,
Vice-Pres. of Merck & Co., who granted permission to select data from
The Merck Index ( Fifth Ed.) and The Merck Manual ( Seventh Ed.),
and of the Science Press and Chas. C. Thomas, Publisher, who allowed
the reprinting of article and text materials; and to express appreciation of
the technical advice of Dr. Dagobert D. Runes.

WILLIAM MARIAS MALISOFF.

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