Observed correlations of Eu/H (Ba/H) with Fe/H for ultra-faint (least massive) dwarf dSph galaxies (upper panel) and faint (less massive: circles) and massive (triangles) dSph galaxies (lower panel). The observed data are assembled from the literature (Frebel et al. 2010; Koch et al. 2013; Shetrone et al. 2001, 2003; Geisler et al. 2005; Cohen & Huang 2009; Letarte et al. 2010; McWilliam et al. 2013). We see no broad increase in the Eu (or Ba: no measurements of the element Eu for ultra-faint dSphs) abundance for less massive dSphs. The average [Eu(Ba)/H] are shown by dashed lines. The high Ba abundance for one star of Ursa Major II can be ascribed to the enrichment by s-process. In the lower panel, we exclude the data of Ursa Minor, which has a compatible feature (Shetrone et al. 2001), but is not supported by Cohen & Huang (2010).