greatest interest: $$\begin{aligned}
\label{approxtheta.eqn} 
\Theta(L_{OH})dL_{OH} &=& 
f_{m}\Phi[L_{60}(L_{OH})]\left(\frac{dL_{60}}{dL_{OH}}\right)dL_{OH}
\\
 &=& Cf_{m}\frac{(\alpha+\beta)}{2}
  \left(\frac{L_{OH}}{L^*_{OH}}\right)^{-\frac{\alpha+\beta+2}{2}} 
  \frac{dL_{OH}}{L^*_{OH}}
\nonumber\end{aligned}$$ Since it is convenient to plot the number of objects per logarithmically spaced bins of luminosity, the number of objects falling in bins of $\Delta L_{OH}=0.1$ Dex centered on $L_{OH}$ can be obtained from $$\begin{aligned}
\hat\Theta(L_{OH}) &=& 
\Theta(L_{OH})\Delta L_{OH} 
\nonumber\\
 &=& \Theta(L_{OH})(10^{0.05}-10^{-0.05}) L_{OH}
\nonumber\\
 &=& 0.231 Cf_{m}\frac{(\alpha+\beta)}{2}
\left(\frac{L_{OH}}{L^*_{OH}}\right)^{-\frac{\alpha+\beta}{2}}
\label{approxlmfnct.eqn} \end{aligned}$$ This function, with $f_m$ set equal to 1, is plotted in Fig. \[OHLumfnct.fig\] for comparison with the result of the numerical integration.

In a related analysis, Baan (1997) presents the 60${\mu}$ FIR luminosity function for OH megamaser sources as a function of $L_{60\mu}$ for direct comparison with the luminosity function for broader population of all FIR galaxies. Baan (1997) further bins the fraction $f_m$ in 0.5 Dex rather than the 1 Dex divisions used in the approximation here. The finer binning would lead to less abrupt inflections in the OH luminosity function derived here (cf. Fig. \[OHLumfnct.fig\]). Overall, there is good agreement between the spatial densities of galaxies between Baan (1997) and the present work, although the fraction of OH galaxies showing megamaser emission presented by Baan (1997) appears to be roughly a factor of two lower 