shows that the effect of dissolved air offsets the effect of pressure on the equilibrium temperature. Air is usually more soluble in uonhydrocarbons and t,, - t , often falls in the range of 0.1-0.2"C for these other organic compounds. An interesting experimental study of the effect of dissolved air on the melting point of cyclohexane has been described by Stokes and Tomlins [J. Chem. Thermodynamics, 6, 379 (1974)l. It is worth remembering that dissolved air affects most physical properties of liquids. Thus when reporting accurate measurements of refractive index, density, viscosity, surface tension, etc., it should be stated whether they refer to the air-free or air-saturated substance. Randolph C. Wilhoit Thermodynamics Research Center Texas A & M University College Station, Texas 7784.1
Vanadium
To the Editor: With reference to the review by N. M. Senozan entitled "Vanadium in the Living World" [J.Chem. Educ., 51, 503 (1974)], it should be noted that the vanadium compound found in the mushroom A. muscaria has been characterized. Vibrational, electronic, and electron spin resonance spectra have established the presence of the VOZi moietyL and degradation studies suggest the formulation as bis(N-hydroxy-~u,rr'-iminodipropionato)O,N-oxovanadium (IV).z The authors do admit the possibility that this complex, which they name amavadin(e), is part of the larger unit in uiuo. 'Bayer, E., and Kneifel, H., Z. Naturfwseh.. 27h, 207 (1972). 2Kneifel, H., and Bayer. E., Angew. C h e m internot. Edn.. 12, 508 (1973).
G. W. Rayner Canham
Bishop's University Lennoxville, P.Q., Canada.
To the Editor: I would like to express my thanks to Professor N. Dennis Chasteen of The University of New Hampshire and to Pmfessor G. W. Rayner Canham for bringing to my attention the two important articles of Bayer and Kneifel. I would also like to mention that a new and intriguing function has been proposed for the vanadium in sea squirts by Dr. Swinehart and his coworkers.' In their work dealing with the metal content of the sea squirts of California they suggest that "a possible role of vanadium (III) in the cells is the production of acid by means of an oxidationreduction cycle." 'Swinehart, J. H., Biggs, W. R., Halko, D. J., Shroeder, N. C.. Bid. Bull., 146, 302 (1974).
N. M. Senozan California State University Long Beach, California 90840 278 / Journal of Chemical Education
