We present deep narrow-band ( = 5390 A, = 77 A) and multi-color observations of the Hubble Deep Field and the Hawaii Deep Field SSA22 obtained with the LRIS instrument at the Keck II 10-m telescope. It is shown that there is a substantial population of galaxies at z 3:4 which can be selected by Ly emission. Comparison with color-selected samples shows that the samples selected with these di ere...
