Abstract
Four different species ofProductus frequently found, in the Lower and Middle Carboniferous of Kashmir show a lineage more or less in the stratigraphical succession. It starts fromProductus cora d'Orb. (the primitive member of this series) and exhibits a retrogressive accentuation of the twisting of the umbo which almost disappeares in the youngest specimens. The spiral angle varies in the four stages from 70° to 30°. The lineage is regarded as a true genetical one.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.