JOINT FILING AGREEMENT

                                                             Page 16 of 19 Pages

                                    EXHIBIT C

                             JOINT FILING AGREEMENT

               The  undersigned  hereby agree that the statement on Schedule 13D
with respect to the Common Stock of Pharmacyclics, Inc. dated March 13, 1997 is,
and any amendments  thereto signed by each of the undersigned shall be, filed on
behalf of each of us pursuant to and in accordance  with the  provisions of Rule
13d- 1(f) under the Securities Exchange Act of 1934.

Date:  March 13, 1997

                                        XXXXX FUND MANAGEMENT LLC


                                        By:  /S/ XXXXXXX X. XXXX
                                             ----------------------------------
                                             Xxxxxxx X. Xxxx
                                             Assistant General Counsel


                                        XXXXXX XXXXX


                                        By:  /S/ XXXXXXX X. XXXX
                                             ----------------------------------
                                             Xxxxxxx X. Xxxx
                                             Attorney-in-Fact


                                        XXXXXXX X. XXXXXXXXXXXXX


                                        By:  /S/ XXXXXXX X. XXXX
                                             ----------------------------------
                                             Xxxxxxx X. Xxxx
                                             Attorney-in-Fact