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Fig. 4


Spectra of He-strong stars for which helium is dominant and carbon is very weak or absent. NIII may be present. The lines marked are HeII λλ 4100, 4200, 4338, 4541, 4686, 4859; NIII λλ 4379, 4511–15, 4640 blend ; HeI λλ 4121, 4144, 4387, 4471, 4713; H λλ 4340, 4861; and λλ 4324, 4509, 4637, 4774 emission.

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