chain of skeletogenic mesenchyme cell aboral chain of skeletogenic mesenchyme cell aboral chain of PMCs dorsal skeletogenic mesenchyme chain The chain of skeletogenic mesenchyme cell that within the subequatorial skeletogenic mesenchyme ring links the two ventrolateral skeletogenic mesenchyme clusters on the aboral side of the embryo. The body rods will be deposited along this cellular strand. dorsal chain of PMCs echinoderm_anatomy