We present very deep HST WFPC2 images in the F814W filter of two Hawaii
Survey fields, SSA13 and SSA22. Using these data with previous ground-based
imaging and spectroscopy, we compare the colors, star-forming properties and
morphologies of the faintest galaxies with a reference sample of bright nearby
galaxies and analyze the changes in field galaxy morphology with magnitude. Our
principal result is the identification of a new morphological class of
``chain'' galaxies at the faintest magnitudes. Based on limited spectroscopy,
we tentatively conclude that these are linearly organized giant star-forming
regions at z=0.5β3 and, if this is correct, that these are large galaxies
in the process of formation.Comment: 18 pages + 1 table of text as 1 LaTeX file (uses aastex style macros:
aaspp.sty, flushrt.sty) plus 1 uuencoded compressed tar file of 12 PostScript
figures (Figs. 3-9, 16-17, and 21-23). The remaining gray-scale plots are
available by anonymous ftp at
ftp://hubble.ifa.hawaii.edu/pub/preprints/plates To appear in the October
1995 Astronomical Journa