It may be called either the subintestinal or splanchnic vein.
Its walls are formed of splanchnic mesoblast with blood-vessels, within which is a lining of hypoblast.
The hepatic diverticula, whatever may be their primitive form, grow into a special thickening of the splanchnic mesoblast.
In the Elasmobranchii the cells forming the vertebral arches are derived from the splanchnic layer of the mesoblastic somites.
The mesenteron consists at first of a simple hypoblastic tube, which however becomes enveloped by a layer of splanchnic mesoblast.
The proctodum is surrounded by a great mass of splanchnic mesoblast.
From the splanchnic layer are formed A great part of the voluntary muscular system.
In my former volume on the Lepadid, I quite misunderstood the course of these splanchnic nerves.
Not only so, but there is at first no marked division into a somatic and splanchnic layer with an intervening body cavity.
The great pair of splanchnic nerves springing from its under side, are here actually twice as large as the circa-sophageal chord.
splanchnic splanch·nic (splāngk'nĭk)
Of or relating to the viscera; visceral.