  Magnetic properties of La$_{1-x}$Ca$_{x}$CoO$_{3}$ (0.10 $\leq x\leq$ 0.25)
are systemically studied in this work. All the samples exhibits the
ferromagnetic state at low temperatures. However, their inverse low-field
magnetic susceptibilities shows a sharply downward deviation from
high-temperature Curie-Weiss paramagnetic behavior well above the ferromagnetic
transition temperature ($T_C$), which indicates the presence of a ferromagnetic
clustered state above $T_C$. A detailed analysis on the susceptibilities
reveals that the short-range state in these Ca-doped samples can be well
described as the Griffiths phase. This characteristic is quite different from
those of the clustered states above $T_C$ recently reported in Sr- and Ba-doped
cobaltites, which are non-Griffith-like. It is proposed that this difference
possibly arises from the unique dependence of magnetic interactions among
Co$^{3+}$ ions on the size of the dopant in the doped cobaltites. Based on
these results, the magnetic diagram of the Ca-doped cobaltites is established.
