The crest seen in the top of the logo is actually Melbourne's coat of arms.
This branding stayed with the bank in the entirety of its first iteration. The bank was bought out by Westpac after they had acquired a larger market share in Victoria. The brand persisted for seven more years, and was eventually rebranded to Westpac in January 2004.
In 2011, Bank of Melbourne was reopened, now as a subsidiary of Westpac. A new logo designed by Ogilvy Australia and Designworks was unveiled as part of the bank's reintroduction. It harkens back to the shield used in the old logo with a navy blue isometric design which reflects the architecture of Melbourne and the colours of Victoria. Many designers felt that the logo was partially inspired by the 2010 City of Melbourne logo.