A STUDY OF NUTS WITH SPECIAL REFERENCE TO 

 MICROSCOPIC IDENTIFICATION. 



INTRODUCTION. 



In connection with the miscroscopical examination of a number of 

 nut products, which have from time to time been brought to the 

 attention of the Bureau of Chemistry, the writer has had occasion 

 to consult the literature of the subject, with the result that little or 

 no reference could be found dealing in a satisfactory way with the 

 microscopical structure of a number of important species of nuts. In 

 this article an attempt has been made to supply the lack of readily 

 accessible information, and hence certain nuts have been omitted, as 

 the chestnut, acorn, beechnut, peanut ; and coconut, good accounts 

 of which are available, 1 as well as some of the rarer nuts which are 

 not often encountered in the American trade. 



Although intended primarily as an account of the minute structure 

 of the nuts examined, occasionally notes of interest or value to the 

 food chemist and others have been added. As a rule, the description 

 of the pericarp was not attempted since this phase of the subject has 

 been well investigated by others. 



Most of the material used for the investigation was purchased on 

 the market or contributed by members of the force of the Micro- 

 chemical Laboratory. Samples of the California black walnut, the 

 pecan, and several varieties of California-grown Persian walnuts 

 were obtained from the growers by R. A. Gould, chief of the San 

 Francisco Laboratory; authentic samples of the two forms of Cali- 

 fornia black walnut were furnished by Ealph E. Smith, superin- 

 tendent of the Southern California Pathological Laboratory ; samples 

 of canarium and cashew nuts were provided by C. F. Langworthy, 

 expert in nutrition investigations, Office of Experiment Stations, 

 while Japanese walnuts and apricot pits were obtained from W. A. 

 Taylor, pomologist, Bureau of Plant Industry. The photomicro- 

 graphs were made by B. J. Howard, chief of the Microchemical 

 Laboratory, aided by the writer. 



1 Winton, Microscopy of Vegetable Foods, 1906, pp. 266-281 ; Hanausek, Microscopy of 

 Technical Products, tr. by Winton and Barber, 1907, p. 387. 



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