Luminosity sequence for moderately luminous B2 stars. Although the wings of the Balmer lines fully justify the luminosity class II for HD 31327, other luminosity criteria (e.g. the ratio of Si III 4552 Å to He I 4387 Å or other metallic to He I lines) show only subtle differences with respect to 9 Cep. The overall spectrum of HD 31327 is much more closely aligned with that of the supergiant than those of the giants. The spectrum of this slow rotator may also be compared to that of HD 250289 (v sin i ≈ 100 km s⁻¹), which may be one of the most luminous Be stars known. The nitrogen lines are unusually weak in this object.