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We discuss near-infrared (NIR) slit spectra of six early-type disk galaxiesin the Virgo Cluster. While the depth of the CO(2,0) band is consistent withthe centers of these galaxies having solar or slightly sub-solarluminosity-weighted metallicities, galaxy-to-galaxy variations in the depth ofthe NaI 2.21um doublet are found, with NaI2.21um lines in three galaxies (NGC4491, NGC 4584, and NGC 4620) that are deeper than those predicted for a solarchemical mixture and a solar-neighborhood mass function. Considering the depthof the NaD lines found by Davidge (2018a), the deep NaI2.21um lines aretentatively attributed to a bottom-heavy mass function. This is counter toobserved trends between mass function slope and velocity dispersion. Two of thethree galaxies with deep NaI2.21um (NGC 4584 and NGC 4620) have Sersicexponents that are consistent with a classical bulge. As for NGC 4491, itscentral NIR spectrum contains prominent emission lines. The relative strengthsof Brgamma and H_2S(1), the presence of [FeII] emission, and the mid-infraredspectral-energy distribution are all consistent with intense recent starformation near the center of that galaxy. Wavelengths that contain theBallick-Ramsey C_2 band at 1.76um are matched by moderately metal-poor E-MILESmodel spectra with an age of 2 Gyr. It is concluded that these galaxies haveevolved in a cluster environment for at least several Gyr.

Intermediate-mass Early-type Disk Galaxies in the Virgo Cluster. II. Near-Infrared Spectra and Evidence for Differences in Evolution