CMNH 12332, Ammonoidea in a concretion.
Locality: Along the Marsyangdi River near the village of Manang, Mustang District, Nepal.
Collector and donor: Chris Mentrek, a Cleveland Heights High School student.
Date collected: Aug. 2, 1999
Cephalopods are extant marine mollusks characterized by tentacles attached to a cone-shaped body. The name cephalopod comes directly from the Greek kephalopoda, “head-feet.” Most fossil cephalopods formed a calcareous shell around their conical body. The shell may be straight, curved, or coiled. As the cephalopod grows, the shell is sectioned and sealed into increasingly large chambers, with the cephalopod remaining connected by soft tissue in a thin tube called the siphuncle. Many cephalopods live today, including cuttlefish, squid, and octopus, but only the nautilus maintains the coiled shell (David and Mapes 1996, “Phylum Mollusca, Class Cephalopoda”). This ammonoid’s diameter: approximately 5.3 cm.
Image by Jacob Kordeleski, CMNH Dept of Archaeology // Hawken School
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