Authors: Alister W. Graham, Helmut Jerjen & Rafael Guzmán
Abstract: We report the discovery of spiral-like structure in Hubble Space Telescope images of two dwarf galaxies (GMP 3292 and GMP 3629) belonging to the Coma cluster. GMP 3629 is the faintest such galaxy detected in a cluster, and it is the first such galaxy observed in the dense Coma cluster. The large bulge and the faintness of the broad spiral-like pattern in GMP 3629 suggests that its disk may have been largely depleted. We may therefore have found an example of the ``missing link'' in theories of galaxy evolution which have predicted that dwarf spiral galaxies, particularly in clusters, evolve into dwarf elliptical galaxies.