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Prudential Stock Index Fund
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Supplement dated December 17, 1999
Prospectus dated November 18, 1999
The following information replaces the information contained on page 21 of
the Prospectus under 'How to Buy, Sell and Exchange Shares of the Fund--How to
Buy Shares--Qualifying for Class A Shares--Other Types of Investors':
Other Types of Investors. Certain officers, employees or agents of Prudential
and its affiliates, Prudential mutual funds, the subadvisers of the Prudential
mutual funds and registered representatives and employees of brokers that have
entered into a selected dealer agreement with the Distributor also may purchase
Class A shares subject to a minimum investment amount of $10,000. To qualify
you must notify the Transfer Agent or your broker at the time of purchase. For
more information, see the SAI, 'Purchase, Redemption and Pricing of Fund
Shares--Class A Shares.'
This information also supplements the 'Share Class Comparison' chart on
page 19 of the Prospectus. For these types of investors, the minimum
purchase amount is $10,000.
The following information supplements the information contained on page 29 of
the Prospectus under 'How to Exchange Your Shares': Participants in any
fee-based and certain other programs for which the Fund is an available option
will have their Class Z shares, if any, exchanged for Class A shares when they
elect to leave such programs. Upon leaving a program (whether voluntarily or
not), such Class Z shares (and, to the extent provided for in the program,
Class Z shares acquired through participation in the program) will be
exchanged for Class A shares at NAV (Net Asset Value). Similarly, participants
in the Prudential Securities 401(k) Plan for which the Fund's Class Z shares
are an available option and who wish to transfer their Class Z shares out of
the Prudential Securities 401(k) Plan following separation from
service (that is, voluntary or involuntary termination of employment or
retirement) will have their Class Z shares exchanged for Class A shares
at NAV.
MF174C1
