The spectral characteristics of the SRd star is Geminorum

Radial velocity measurements of the SRd star IS Geminorum indicate a small variability (with an amplitude of about 15 km s^–1) with a time-scale of a few tens of days. The spectrum of this star does not show any peculiarity (i.e., emissions, variation in intensity of spectral features, weak metal lines). This fact casts doubts on the homogeneity of the SRd class. The possible subdivision of it between two different types of objects, one of Population I and the other of Population II is pointed out.