develops from ends during starts during posterior cardinal vein intersomitic vessel intersomitic vein xenopus_anatomy 2011-08-30T02:26:59Z Type of vein that sprouts from the posterior cardinal vein, growing dorsally between the somites, and then joining, and draining the dorsal longitudinal anastomosing vessel. XAO:0004164 lab NF stage 35 and 36 NF stage 47