sentences:  Lang (1945) had it as an epidermal layer, similar to the waxy cuticle of plants today, covering a parenchymatous layer.Alternatively, Edwards (1982) proposed that the inner tissue of "Nematothallus" comprised stringy tubes, with the cellular patterning produced by their ends.The genus was later formalised by Strother, who discovered better preserved and more complete specimens in Pennsylvania, America – which appear to show tubes connected to the rims of cuticle.