  We have obtained new photometry and intermediate resolution ($\Delta \lambda
= 2.7$ \AA\ ) spectra of 19 of these objects
  (14.9 $\le$ $I_c$ $\le$ 17.5) in order to confirm cluster membership. We
identify 15 of our targets as likely cluster members based on their $VRI$
photometry, spectral types, radial velocity, and H$\alpha$ emission strengths.
Higher S/N spectra were obtained for 8 of these probable cluster members in
order to measure the strength of the lithium 6708 \AA\ doublet and thus obtain
an estimate of the cluster's age. One of these 8 stars has a definite lithium
detection and two other (fainter) stars have possible lithium detections. A
color-magnitude diagram for our program objects shows that the lithium
depletion boundary in IC~2391 is at $I_c$=16.2. Using recent theoretical model
predictions, we derive an age for IC~2391 of 53$\pm$5 Myr. While this is
considerably older than the age most commonly attributed for this cluster
($\sim$35 Myr) this result for IC~2391 is comparable those recently derived for
the Pleiades and Alpha Persei clusters and can be explained by new models for
high mass stars that incorporate a modest amount of convective core
overshooting.
