MARINE LIFE IN THE CAMBRIAN PERIOD

1 and 8, Jellyfishes; 2, Hyolithes (swimming snail); 3, Humenocaris; 4, Protospongia; 5, Lampshells (Obolella); 6, Orthoceras; 7, Trilobite (Paradoxides) — see fossil on page 13; 9, Coral (Archæocyathus); 10, Bryograptus; 11, Trilobite (Olenellus); 12, Palesterina

Then, as we come up the record, signs of past life appear and increase. The age of the world?s history in which we find these past {13} traces is called by geologists the Lower Palæozoic age. The first indications that life was astir are vestiges of comparatively simple and lowly things: the shells of small shellfish, the stems and flowerlike heads of zoophytes, seaweeds and the tracks and remains of sea worms and crustacea. Very early appear certain creatures rather like plant-lice, crawling creatures which could roll themselves up into balls as the plant-lice do, the trilobites. Later by a few million years or so come certain sea scorpions, more mobile and powerful creatures than the world had ever seen before. r6r5sc6A8vqsDp1Gkkw79zqoMCu9sPUxd7tNZJrD3dtMSSFbNrADnPsdwAbl90R5