Infrared observations at an effective wave Length of 3.5u of a selected group of Long Period Variable (LPV) stars are presented. Mira type acmiregular stars of M, S, and C spectral classifications are monitored throughout the full cycle of variability. Although the variable infrared radiation doe not exactly repeat in intensity or time, the regularity is sufficient to produce mean 3.5u light curves. For the M, S, and C stars as a group, the moan 3.5U alterations are about 0.7. The 3.5u maximum radiation lags the visual maximum by about one seventh of a cycle, while the minimum 3.5u intensity occurs nearly one-half cycle after infrared maximum. In some stars, there are inflexions or humps on the ascending portion of the 3.5u light curve which may also be seen in the visual variations.
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