Filed by The PNC Financial Services Group, Inc.
                      Pursuant to Rule 425 under the Securities Act of 1933 and
    deemed filed pursuant to Rule 14a-12 of the Securities Exchange Act of 1934

                             Subject Company: Mercantile Bankshares Corporation
                                                     Commission File No. 0-5127

     On October 11, 2006, the following letter from James E. Rohr, Chairman and
Chief Executive Officer of The PNC Financial Services Group, Inc., was provided
to the employees of Mercantile Bankshares Corporation:

James E. Rohr
Chairman and Chief Executive Officer

[PNC LOGO]

October 11, 2006

All of us at The PNC Financial Services Group are delighted about the plans to
combine our organizations.

By establishing deep and lasting customer relationships, Mercantile has built a
premier franchise with an outstanding record of growth. Your strengths -
particularly in retail banking, commercial banking and wealth management - and
impressive distribution network nicely complement those of PNC. Even more
important, we share a culture that emphasizes exceptional customer service and
devotion to the community. I am confident that, together, we will have an
opportunity to become a dominant bank in the highly coveted New
Jersey-to-Washington corridor.

Over the next several months, representatives of PNC will work closely with a
team from Mercantile to plan for our future. This spirit of cooperation has
enabled us to successfully complete many mergers and expand our franchise,
including our entry into Greater Washington last year. We have found that by
working together we can minimize disruptions during the transition and maximize
the benefits for customers and employees over the long term.

We understand that you may have questions about PNC. Enclosed are some materials
to familiarize you with our company.

We are excited about the opportunity we have to build on our combined strengths
and





create one of the nation's leading financial services companies.

Sincerely,

/s/ James E. Rohr

ADDITIONAL INFORMATION ABOUT THIS TRANSACTION

The PNC Financial  Services Group,  Inc. and Mercantile  Bankshares  Corporation
will be  filing  a  proxy  statement/prospectus  and  other  relevant  documents
concerning the merger with the United States Securities and Exchange  Commission
(the "SEC").  WE URGE INVESTORS TO READ THE PROXY  STATEMENT/PROSPECTUS  AND ANY
OTHER  DOCUMENTS  TO BE FILED  WITH THE SEC IN  CONNECTION  WITH THE  MERGER  OR
INCORPORATED BY REFERENCE IN THE PROXY  STATEMENT/PROSPECTUS,  BECAUSE THEY WILL
CONTAIN IMPORTANT INFORMATION.

Investors will be able to obtain these documents free of charge at the SEC's web
site  (www.sec.gov).  In  addition,  documents  filed  with  the  SEC by The PNC
Financial Services Group, Inc. will be available free of charge from Shareholder
Relations  at  (800)  843-2206.  Documents  filed  with  the  SEC by  Mercantile
Bankshares  will  be  available  free  of  charge  from  Mercantile   Bankshares
Corporation,  2  Hopkins  Plaza  P.O.  Box  1477,  Baltimore,   Maryland  21203,
Attention: Investor Relations.

The directors,  executive officers,  and certain other members of management and
employees of Mercantile  Bankshares  are  participants  in the  solicitation  of
proxies in favor of the merger from the  shareholders of Mercantile  Bankshares.
Information about the directors and executive officers of Mercantile  Bankshares
is set forth in the proxy statement for its 2006 annual meeting of stockholders,
which was filed with the SEC on March 29, 2006. Additional information regarding
the   interests   of  such   participants   will  be   included   in  the  proxy
statement/prospectus  and the other relevant  documents  filed with the SEC when
they become available.