PRO plotspec, specwav, specflx, xlo, xhi, ylo, yhi

; establish the box
plot, [xlo,xhi],[ylo, yhi],  $
     xrange=[xlo,xhi], yrange=[ylo,yhi], xtitle='Wavelength ' +string("305B), ytitle='Normalized Flux',xstyle=1, ystyle=1,charsize=1.3,charthick=1.0, /nodata  

oplot, specwav, specflx, psym=10, thick=2  ; plot the spectrum
oplot, [xlo,xhi], [1,1], linestyle = 1    ; mark the continuum
;oplot, [xlo,xhi], [0.4,0.4], linestyle = 0    ; mark the continuum

END