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their geographical location, or their adaptation to special environments, 

 Some of the most interesting species were available only in remote parts 

 of the earth and at particular seasons o A few of these were collected 

 by interested colleagues and shipped via air mail, A few species, par- 

 ticularly green, chysophycean, and blue-green algae, were cultured. 

 Some species, particularly some of the xanthophyoeae of the genus 

 Vau cheria, were found only after numerous collection trips in the vi- 

 cinity of Stanford and et Hawaii » 



For examination of the pigments, only mature, green tissues were 

 selected. These tissues, as fronds and leaves, were handled carefully 

 so that they were not damaged by storage, wilting or freezing before 

 extraction of the pigments. 



Algae collected in the field were examined for contamination by 

 other species o They were washed thoroughly with water to remove extra- 

 neous organisms and then blotted with a towel. Unicellular algae grown 

 in liquid culture media were collected in centrifuge tubes. Various 

 species grown on agar gels were washed loose with water and then col= 

 lected in centrifuge tubes. All these unicellular species were ex- 

 tracted in the centrifuge tubes. 



In cultures of certain unicellular algae, some of the cells ap^ 

 peared to be yellower than others as if all were not growing at the 

 same rate. These cultures yielded reduced quantities of the typical 

 chloroplast pigments, and cultures of some organisms, Protosiphon and 

 Anki strode smus, yielded new carotenoid pigments that were not present 

 in the rapidly growing, deep green cultures, (See seotion on green 

 algae,) 



