66 CARNEGIE INSTITUTION OF WASHINGTON. 



Vitamin Notes, by H. W. Fenner. 



The investigations of Eykmann, Funk, and others which resulted 

 in the discovery of an unknown essential factor in our food playing a 

 very important role in metabolism, and in 1911 named "vitamin" 

 by Funk, have so changed our ideas of the relative value of many of our 

 foods that the subject has become one of great interest, not only to 

 the investigator but to the general public, by reason of its apparent 

 importance both to health and to economic considerations, 



AH vitamins are derived, either directly or indirectly, from plant 

 life, and up to the present time our inability to easily determine the 

 value in vitamins of the various vegetables and plants, to extract, 

 analyze, and preserve these vitamins, and to determine exactly what 

 they are and their role in metabolism has, in our daily routine of work, 

 constantly brought before us questions that seem to be correlated 

 with that of vitamins. 



In May of this year, in an attempt to aid in elucidating some of 

 these questions, a series of experiments was started, using albino rats 

 as subjects, investigating particularly the vitamin content of some of 

 the commoner food vegetables, such as tomatoes, carrots, sweet 

 potatoes, etc., and sprouted seeds of wheat and beans. These inves- 

 tigations are still under way. 



Many difficulties have been met in arriving at some means of con- 

 centrating and preserving the B and C vitamins. At present no 

 procedure has been worked out that is entirely satisfactory, but our 

 records are commencing to show some comparative values in vitamin 

 content and general nutritional value, these values appearing to be con- 

 siderably at variance with many of our accepted conclusions. However, 

 the time is all too short and the results too indefinite to warrant our 

 making a full repbrt at this time. Undoubtedly, considerable time 

 will be required to form any conclusions that may be considered 

 authentic. 



PHYTOGEOGRAPHY AND ECOLOGY. 

 Vegetation of a Desert Valley, by Forrest Shreve. 



Work on the vegetation and physical conditions of the Avra Valley 

 and adjacent areas has been chiefly directed, during the past year, to a 

 study of the several soils which the area presents. Additional me- 

 chanical analyses have been made in order to secure a more precise 

 knowledge of the distribution of the soil types, particularly in areas 

 where previously determined relations between soils and vegetation 

 did not seem to hold true. The march of soil-moisture was followed 

 in the various soils through the arid fore-summer of 1921, which was 

 characterized by very low percentages as a result of the deficient rain- 

 fall of the winter 1920-21, the moisture in sandy outwash having 

 fallen to 1.5 per cent at 15 cm. by February 1. Measurements of the 



