SWIITHSONIAM MISCELLANEOUS COLLECTIONS, VOL. 137 



RICHARDS AND PIPA, PL. 2 



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I, Higli-magnification electron-microscope picture of particles that may he 

 cliitin micelles in a partly decomposed air-sac (tracheal) memhrane. 2, High- 

 magnification electron-microscope picture of a granular membrane (granules- 

 micelles ? ) showing alignment of particles leading to formation of microfibers. 

 A'Taterial transformed to chitosan and stained with ZrCU. From ecdysial mem- 

 hrane of a moth pupa (Richards, 1955). 3. Lower-magnification electron-micro- 

 scope picture of clear chitin microfibers from pepsin-digested ecdysial membrane 

 (Richards, 1955). 4, Adlineation of microfibers into larger fibrillar bundles in 

 membrane purified to chitin with hot lo-percent NaOH. 



