1213Fresh sections of collenchyma were treated with Schweitzer's reagent (8) in the customary manner. By this treatment the cellulose con'stituents were removed, leaving the pectic compounds intact. After this treatment the sections showed the absence of cellulose by the same four tests used above (8). Figure 16A is the bright-field image of the collenchyma treated for the removal of cellulose and B is the Spierer image. The Spierer image of this section, containing no cellulose, cannot be distinguished from the one in which cellulose is known to be present as distinct lamellas (Figure 15 B). ACKNOWLEDQMENTThe authors are indebted to A. G. Lang for assistance with the botanical material here reported. LITERATURE CITBDAnderson, D. B., Sitrbe-r. Akad. Wiss. Wien, Math.-naturw.

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