The mid-Ordovician observed the primary cephalopods with septa sturdy ample to cope Using the pressures related to further drinking water, and could inhabit depths larger than one hundred200 m.[139] The direction of shell coiling would verify being vital to the future results in the lineages; endogastric 메이저사이트 coiling would only permit substantial dimension to be attained that has a straight shell, whereas exogastric coiling in the beginning relatively