762 EXPERIMENT STATIOX RECORD. [Vol.35 



eluded in the study. The method employed was found to be accurate to 0.000003 

 gm. of iodin. The results of the experiments are presented in three tables as 

 follows : An alphabetical list of the foods, showing the number of samples 

 analyzed, the number containing iodln, and the maximum iodin content; a 

 grouping of the foods according to their general class or characteristic ; and a 

 grouping of the foods according to geographical location of the source of the 

 samples. 



The following groups of foods are arranged in the order of increasing abund- 

 ance of iodin, the first mentioned being that in which it is most rarely found : 

 Nuts ; spices, condiments, and stimulants ; fruits ; cereals ; hays, silage, and 

 forage crops ; garden vegetables and root crops ; leguminous seeds ; animal 

 products ; manufactured foods and milling and manufactory by-products ; and 

 seaweeds. It was usually found in exceedingly small quantities, is by no means 

 a constant constituent of foods, and is deemed, in most cases at least, strictly 

 an accidental constituent. 



Traces of iodin were found in butter, in eggs, and in several kinds of meat 

 and fish, but none was found in 18 samples of cow's milk. Among the garden 

 vegetables and root crops traces of iodin were found in beets, cucumbers, celery, 

 onions, potatoes, and spinach. 



" Of the hays, silage, and forage crops about 1 sample in 4 contained iodin. 

 Among leguminous seeds iodin was found in 11 samples out of 32 ; more com- 

 monly among beans, peas, and cowpeas than among soy beans. 



" The manufactured foods and milling and manufactory by-products contained 

 iodin in 13 samples out of 25; of those containing iodin 10 were made from 

 cereals. The offal parts of the grains are richer in iodin than are the more 

 starchy parts. 



"Agar agar and Irish moss (used in making blanc mange) were richer in 

 iodin than any other products examined." 



No iodin was found in 7 kinds of nuts examined and none in 16 samples of 

 table salt. 



" The more important sources of iodin in the human dietary . . . [aside 

 from Irish moss] are the garden vegetables, though some is also found in the 

 cereal foods, and in several foods of animal origin, mostly of the sorts less com- 

 monly used. Among the foods used by live stock the more important sources of 

 iodin are the hay, silage, and forage crops, and also the milling and manu- 

 factory by-products, comparatively little being found in the natural grain 

 foods." 



While iodin was found to be more commonly present in foods from some re- 

 gions than from others, no general geographical distribution of iodin in foods 

 was discovered, and the iodin content of samples of the same food products from 

 the same field often varied widely. " None of the ordinary methods of fertiliza- 

 tion, or other details of management of the soil have been found, in any regular 

 way, to affect the iodin content of field crops." 



No relationship between the iodin content of foods and the prevalence of goiter 

 was discovered. 



An earlier report of this investigation has been noted (E. S. R., 35, p. 555). 



The iodin content of foods, E. B. Forbes, F. M. Beegle, et al. {Jour. Med. 

 Research, S4 {1916), No. 3, pp. U5-^58).— The bulk of the material in this 

 article is noted above. 



Digestibility of very young veal, C. F. Langworthy and A. D. Holmes 

 (17. S. Dept. Agr., Joiir. Agr. Research, 6 {1916), No. 16, pp. 577-5S8).— This 

 series of exi^eriments was undertaken to determine the completeness of diges- 

 tion of very young or " bob " veal by human subjects. 



