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We present Atacama Large Millimeter/submillimeter Array (ALMA) Cycle 2observations of CO(2-1) emission from the circumnuclear disks in two early-typegalaxies, NGC 1380 and NGC 6861. The disk in each galaxy is highly inclined($i\,{\sim}\,75^{\circ}$), and the projected velocities of the molecular gasnear the galaxy centers are ${\sim}300\,\mathrm{km \, s^{-1}}$ in NGC 1380 and${\sim}500\,\mathrm{km \, s^{-1}}$ in NGC 6861. We fit thin disk dynamicalmodels to the ALMA data cubes to constrain the masses of the central blackholes (BHs). We created host galaxy models using Hubble Space Telescope imagesfor the extended stellar mass distributions and incorporated a range ofplausible central dust extinction values. For NGC 1380, our best-fit modelyields $M_{\mathrm{BH}} = 1.47 \times 10^8\,M_{\odot}$ with a ${\sim}40\%$uncertainty. For NGC 6861, the lack of dynamical tracers within the BH's sphereof influence due to a central hole in the gas distribution precludes a precisemeasurement of $M_{\mathrm{BH}}$. However, our model fits require a value for$M_{\mathrm{BH}}$ in the range of $(1-3) \times 10^9\,M_{\odot}$ in NGC 6861 toreproduce the observations. The BH masses are generally consistent withpredictions from local BH-host galaxy scaling relations. Systematicuncertainties associated with dust extinction of the host galaxy light andchoice of host galaxy mass model dominate the error budget of bothmeasurements. Despite these limitations, the measurements demonstrate ALMA'sability to provide constraints on BH masses in cases where the BH's projectedradius of influence is marginally resolved or the gas distribution has acentral hole.

Black Hole Mass Measurements of Early-Type Galaxies NGC 1380 and NGC 6861 Through ALMA and HST Observations and Gas-Dynamical Modeling