The first Ediacaran fossils discovered were the disc-shaped "Aspidella terranovica" in 1868. Their discoverer, Scottish geologist Alexander Murray, found them useful aids for correlating the age of rocks around Newfoundland. However, since they lay below the "Primordial Strata" of the Cambrian that was then thought to contain the very first signs of animal life, a proposal four years after their discovery by Elkanah Billings that these simple forms represented fauna was dismissed by his peers. Instead, they were interpreted as gas escape structures or inorganic concretions. No similar structures elsewhere in the world were then known and the one-sided debate soon fell into obscurity. In 1933, Georg Gürich discovered specimens in Namibia but the firm belief that complex life originated in the Cambrian led to them being assigned to the Cambrian Period and no link to "Aspidella" was made. In 1946, Reg Sprigg noticed "jellyfishes" in the Ediacara Hills of Australia's Flinders Ranges but these rocks were believed to be Early Cambrian so, while the discovery sparked some interest, little serious attention was garnered.