Blue X-shooter spectrum of the PMS stars. The spectrum is stacked over all epochs and shows Balmer lines (green labels) and He I lines (orange labels). The remaining features are marked in blue. B337 is not detected in the blue due to the high extinction. The spectra of B215 and B289 were not nebula-subtracted. A sharp emission feature is present in addition to the hydrogen features. The ratio of the Mg II 448.1 nm (blue label) and He I 447.1 nm line changes with spectral type. A strong DIB is present at 443 nm (blue label).