Analysis of the stratigraphic position of 44 steep-sided domes in a global band of C1-MIDRs at 30 ¿N latitude shows that in a region representing over 11% of the surface of Venus, the vast majority of steep-sided domes are closely associated stratigraphically with shield plains (Psh), a unit characterized by a very high abundance of small shields of apparent basaltic extrusive origin. Previously reported heterogeneities in areal and altitude distribution are now more plausibly interpreted in terms of formation in association with this unit and burial by subsequent regional plains units. Measurement of abundances of steep-sided domes presently exposed in shield plains and extrapolation to areas below younger units suggest that over a thousand of these features may have formed originally. Interpretation of the mode of formation of the steep-sided domes in the context of these new data favors hypotheses for their origin which call on remelting of basaltic crust to produce more silica-rich magmas. Occurrences of some steep-sided domes in association with summits of large shields (e.g., Tepev Mons and Sapas Mons) indicate that other mechanisms of dome formation (e.g., evolution of magma reservoirs) have also operated at other times in the history of Venus. ¿ 1999 American Geophysical Union