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New 3.3--3.6~$\mu$m spectra were obtained of nine young stellar objectsembedded in molecular clouds. An absorption feature at $\sim$3.47~$\mu$m(2880~cm$^{-1}$) with FWHM$\sim$0.09 $\mu$m (80 cm$^{-1}$), first identified byAllamandola et al. (1992), was definitively detected toward seven objects, andmarginally in the other two. The feature is better correlated with H$_2$O icethan with the silicate dust optical depth in the data obtained to date.Assuming the feature is due to a C--H stretch absorption, the abundance of theC--H bonds averaged along the lines of sight is closely related to that ofH$_2$O ice. We interpret the correlation with H$_2$O ice as indicating that theC--H bonds form together with H$_2$O ice on grain surfaces in the molecularclouds, though other formation mechanisms are not ruled out. A secondabsorption feature at 3.25 $\mu$m (3080 cm$^{-1}$) was detected towardNGC7538/IRS 1 and S140/IRS 1; this feature was first detected in spectra ofMonR2/IRS 3 (Sellgren, Smith, \& Brooke 1994; Sellgren et al. 1995). There isas yet insufficient data to tell whether this feature is better correlated withH$_2$O ice or silicates.Comment: 20 pages (37 kb), AASTex format. Also 9 Postscript figures (388 kB),  tarred, compressed and uuencoded, added with 'figure' command. 9 figures  (compressed PostScript) available from anonymous ftp at  ftp://bessel.mps.ohio-state.edu/pub/sellgren/brookefig.tar.Z A complete  (text+figs) compressed PostScript preprint is also available at  ftp://bessel.mps.ohio-state.edu/pub/sellgren/brooke.ps.Z Hardcopy available  upon request to tyb@scn5.jpl.nasa.gov. Accepted by ApJ (March 1996

A Study of Absorption Features in the 3 Micron Spectra of Molecular Cloud Sources with H 2O Ice Bands