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The absorption spectrum of $BI3$ in the gaseous state showed a strong continuum in the region from A3150 to about $2500\backslash AA$. This continuum, due to the molecule $BI3$ is in agreement with the value extrapolated from the known known continua of the related trihalides of boron and $aluminum.1$ Following Schumb, Gamble, and $Banus,2$ the lower iodides of boron were prepared in the absorption cell by passing an electrodeless discharge through $BI3$ vapor. The absorption spectra of these lower iodides of boron revealed the existence of four continua in the regions $\lambda 2508-2790\backslash AA,\lambda 2821-2985\backslash AA,\lambda 3040-3203\backslash AA$, and $\lambda 3376-3585\backslash AA$. Of the continuum in the region $\lambda 3376-3585\backslash AA$ is the strongest, with a maximum at $\lambda 3456\backslash AA$. and the $\lambda 3040-3203\backslash AA$ continuum is the weakest. Previous work on the spectra of the diatomic halides of group III $elements3$ has shown that the strongest continuum can be attributed to the diatomic molecule BI. It represents a $\mathrm{<mrow\; data-mjx-texclass="ORD">1</mrow>}\Pi -1\Sigma$ transition, with the upper $\mathrm{<mrow\; data-mjx-texclass="ORD">1</mrow>}\Pi$ state repulsive. The dissociation energy of BI is approximately 3,5 ev if in its repulsive state it dissociates to $B(2P1/2)$ and $1(2P3/2)$, the lowest of the atomic states. If the molecule dissociates to $B(2P1/2)$ and an excited $I(2P1/2)$, then the dissociation energy is approximately 2.5 ev.