Supplement to Prospectus Dated May 1, 1998
                       Supplement dated December 31, 1998

This Supplement should be retained with the current Prospectus for your variable
annuity  contract  issued  by  American   Skandia  Life  Assurance   Corporation
("American  Skandia").  If you do not have a current prospectus,  please contact
American Skandia at 1-800-SKANDIA.

                   A. CHANGES TO VARIABLE INVESTMENT OPTIONS

1.   Effective  January  1,  1999  Janus  Capital  Corporation  will  be the new
     portfolio sub-advisor for the Founders Capital Appreciation  portfolio.  In
     connection with this change the  portfolio's  name is changed to "AST Janus
     Small-Cap Growth."

The following information is added to the table entitled "Underlying Mutual Fund
Portfolio Annual Expenses (as a percentage of average net assets)":



                                   Management              Management         Other          Other      Total Annual    Total Annual
                                       Fee                     Fee          Expenses       Expenses       Expenses        Expenses
                                    after any              without any      after any     without any     after any      without any
                                   applicable              applicable      applicable     applicable     applicable      applicable
                                 reimbursement           reimbursement   reimbursement  reimbursement  reimbursement   reimbursement

- ------------------------------------------------------------------------------------------------------------------------------------
American Skandia Trust
                                                                                                          
AST Janus Small-Cap Growth1            N/A                   0.90%              N/A          0.23%             N/A          1.13%


(1) Prior to January 1, 1999, the Investment  Manager had engaged Founders Asset
Management,  LLC as Sub-advisor for the Portfolio (formerly the Founders Capital
Appreciation portfolios).

GAL3 (12/98)

The Expense  Examples for the new AST Janus  Small-Cap  Growth 3 sub-account are
the  same as the  expense  examples  for the  Founders  Capital  Appreciation  3
sub-account within the Prospectus dated May 1, 1998.


The following is added to the section entitled  "INVESTMENT OPTIONS - Underlying
Mutual Fund: American Skandia Trust":

Sub-account                                     Underlying Mutual Fund Portfolio
AST Janus Small-Cap Growth 3                          AST Janus Small-Cap Growth


2.   Effective  December  31, 1998,  each  portfolio of AST will have the prefix
     "AST"  added to the  portfolio  name.  The AST  prefix  will  appear on the
     effected  portfolio(s) on all statements and reports for periods  beginning
     on or after January 4, 1999. The names of the respective  sub-accounts  are
     changed accordingly.

     Effective December 31, 1998, the name of the Neuberger&Berman Mid-Cap Value
     portfolio  of  AST  is  changed  to  AST  Neuberger  Berman  Mid-Cap  Value
     portfolio.  The name of the  sub-account  is changed  accordingly.  The new
     portfolio and  sub-account  name will appear on all  statements and reports
     for periods beginning on or after January 4, 1999.

                       B. SHORT DESCRIPTIONS - APPENDIX B

The following short  description of the AST Janus Small-Cap  Growth Portfolio is
to be added:

AST Janus Small-Cap Growth Portfolio:
The investment objective of the Portfolio is capital appreciation. The Portfolio
pursues its objective by normally  investing at least 65% of its total assets in
securities issued by small-sized companies. Small-sized companies are those that
have market  capitalizations  of less than $1.5 billion or annual gross revenues
of less than $500  million.  Companies  whose  capitalization  or revenues  fall
outside  these  ranges after the  Portfolio's  initial  purchase  continue to be
considered  small-sized for the purposes of this policy.  The Portfolio may also
invest in stocks of larger companies with potential for capital appreciation.

The Portfolio  will invest  substantially  all of its assets in common stocks to
the extent the Sub-advisor  believes that the relevant market environment favors
profitable  investing in those  securities.  The  Sub-advisor  generally takes a
"bottom up" approach to building  the  Portfolio.  In other  words,  it seeks to
identify  individual  companies with earnings  growth  potential that may not be
recognized by the market at large.  Although themes may emerge in the Portfolio,
securities are generally  selected without regard to any defined industry sector
or other similarly defined selection  procedure.  Realization of income is not a
significant investment consideration.

Because the Portfolio invests  primarily in common stocks,  the fundamental risk
of  investing  in the  Portfolio  is that the value of the stocks it holds might
decrease.  Smaller  or newer  issuers,  such as those  in  which  the  Portfolio
invests,  are more likely to realize more  substantial  growth as well as suffer
more significant losses than larger or more established issuers.  Investments in
such companies can be both more volatile and more speculative.  The Portfolio is
designed  for  long-term  investors  who seek capital  appreciation  and who can
tolerate the greater risks  associated with  investments in foreign and domestic
common stocks. The Portfolio is not designed as a short-term trading vehicle and
should not be relied upon for short-term  financial needs. The Sub-advisor tries
to reduce the risk of the Portfolio through  diversification  of the Portfolio's
assets,  so that the effect of any single holding on its overall portfolio value
is reduced. In addition,  the Portfolio will not invest 25% or more of its total
assets in any particular industry (excluding U.S. government securities).