The expansion chamber method is used to obtain tracks of protons ejected in 67 disintegrations of fluorine and 121 disintegrations of neon while both gases are under $\alpha$-particle bombardment. The energetics of the reaction are in good agreement with the mass data, and protons corresponding to transitions to the ground state of the residual nuclei are found with both elements. No disintegrations are detected until the energies of the $\alpha$-particles reach 3.7 and 4.4 Mev in fluorine and neon, respectively. These are the only energy levels recorded.

The ranges of the protons from fluorine vary within wide limits (an indication of several excited states of the residual nucleus), while those from neon show only one range corresponding to the ground state. In all cases the angular distribution of the ejected protons is anisotropic, and evidence is given that the low energy $\alpha$-particles responsible for the disintegrations all make off-center collisions and therefore possess angular momentum about the nuclear center. A simple model of the collision process is suggested to account for these results and also for the relative yields which are in the ratio 1:0.5:2 for nitrogen, fluorine, and neon, respectively. A possible cause of the apparent disintegration of nitrogen by $\alpha$-particles of very low energy is discussed.

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