SCHEDULE 14A

                              (Rule 14a-101)

                  INFORMATION REQUIRED IN PROXY STATEMENT
                         SCHEDULE 14A INFORMATION

             Proxy Statement Pursuant to Section 14(a) of the
                      Securities Exchange Act of 1934

Filed by the registrant  X
Filed by a party other than the registrant  __
[ ]_  Preliminary proxy statement            [ ] Confidential, For Use of the
                                                 Commission Only (as permitted
                                                 by Rule 14a-6(e)(2))
[ ]   Definitive proxy statement
[x]   Definitive additional materials
[_]   Soliciting material pursuant to Rule 14a-11(c) or Rule 14a-12

                       McDonnell Douglas Corporation
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             (Name of Registrant as Specified in Its Charter)
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       (Name of Person(s) Filing Proxy Statement, if other than Registrant)

Payment of filing fee (Check the appropriate box):

[X] No fee required
[ ] Fee computed on table below per Exchange Act Rules  14a-6(i)(l) and 0-11 (1)
  Title of each class of securities to which transaction applies:

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  (2)  Aggregate number of securities to which transaction applies:

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  (3) Per unit price or other underlying value of transaction  computed pursuant
to  Exchange  Act Rule 0-11 (set  forth the  amount on which the  filing  fee is
calculated and state how it was determined):

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[ ]    Fee paid previously with preliminary materials.

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[ ] Check box if any part of the fee is offset as provided by Exchange  Act Rule
0-11(a)(2)  and  identify  the  filing  for  which the  offsetting  fee was paid
previously.  Identify the previous filing by registration  statement  number, or
the Form or Schedule and the date of its filing.

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                                VOTE YOUR SHARES

                 Return Ballots by Mail to Have a Say on Merger


If you  own  McDonnell  Douglas  stock  through  either  the  Employee  Savings,
Investment  and Thrift  Plans  (savings  plans) or the  employee  Payroll  Stock
Ownership  Plan (PAYSOP) and you want to vote on the pending merger with Boeing,
you must complete a voter instruction card.

The card must be signed and mailed to the  trustee of those  plans in time to be
received by July 22.  Teammates or retirees with stock in these plans may attend
the  special  shareholders  meeting  July 25 in St.  Louis  but can vote only by
mailing in signed voter instruction cards.

A card  and a  business-reply  envelope  has  been  mailed  with a  joint  proxy
statement/prospectus to each participant in the savings plans and the PAYSOP.

Participants'  votes will be counted  differently  for the savings plans and the
PAYSOP.

Shares held by employees or retirees,  who own stock  through the savings  plans
and who do not return a signed card in time,  will be voted by the plan trustee,
said Judi Kapeller,  senior  specialist of shareholder  services.  The trustee's
vote will be cast -- for, against and in abstention -- in the same proportion as
the votes cast by shareholders who return their ballots by the July 22 deadline.

Participant  shares in the PAYSOP for which a signed voter  instruction  card is
not received by the deadline  will not be voted.  Kapeller  cautioned  that such
"nonvotes"  would  actually  have the same  effect as votes  against  the merger
proposal because, to be approved, the proposal must receive the affirmative vote
of holders of two-thirds of all outstanding  McDonnell  Douglas  shares.  If the
vote is close, the number of unvoted shares could tip the balance, she noted.

Employees  or  retirees  who also own stock  through an  account  with a bank or
broker (a "street"  account) or directly in their own names will  receive in the
mail separate  instructions for voting those shares. A "nonvote" of these shares
also would have the same effect as a vote against the merger proposal.

About 18 percent of McDonnell  Douglas  shares are owned by teammates,  Kapeller
said.  More than 80 percent of  employees  own their  stock  through the savings
plans and PAYSOP.  Historically,  less than 26 percent of  employees  vote their
shares.

Teammates  who want to attend the special  shareholders'  meeting  should send a
written  request for an  admittance  ticket to Judi  Kapeller at M/C  S100-1240.
Include your name, address and employee number. E-mail or fax requests will also
be accepted. The fax number for such requests is (314) 777-1007.

To attend the meeting, retirees should follow the instructions they receive with
their joint proxy statement/prospectus.

     
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Shares You Own Personally or Through PAYSOP:  `If you don't vote,  you're voting
no.'
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Shares You Own Through Savings Plans: `If you don't vote,  someone else will, in
effect, vote your shares.'

Jim Palmer
Chief Financial Officer


     
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Savings Plans -- Plans that allow employees to have a percentage of their weekly
pay  contributed  to the plan and invested into selected  fund(s).  Participants
with contributions  (employee or company match) in Fund D, the McDonnell Douglas
stock     fund,      are     eligible     to     vote     on     the     merger.
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PAYSOP -- A company-funded McDonnell Douglas stock ownership plan for employees,
which was in effect only from 1983 through 1986.