[gradsusr] problem with a .ctl script

[Ismaila Diallo]

Dear Grads User's.

i wrote a .ctl script, when opening the .ctl i get this error: 
 open bignona.ctl
Scanning description file:  bignona.ctl
Open Error:  Looking for "endvars", found "envards" instead.
  --> The invalid description file record is: 
  --> envards
  The data file was not opened. 

the ctl script is :

DSET   ^extarc_bi.dat
DTYPE  station 
options big_endian
undef -1.e34
TITLE  extract_obs_bignona
xdef  1 linear -17.5 1
ydef  1 linear 15.30 1
zdef 1 levels 1000 
TDEF  6575 Linear 01jan1991 1dy
VARS 1
tpr  0 99 precipitation (mm/jr)
envards


Could anyone help me to resolve this error.

Sincerely
Ismaial