Abstract

AbstractThe fully formed chondrocranium of the Egyptian snake, Psammophis sibilans has been described in detail. The tectum synoticum is very broad and there is apparently no tectum posterius. The notochord is completely embedded in the occipital condyle. The connection between the condyle and the odontoid process persists to the fully formed stage. There is only one commissure, representing the anterior basicapsular commissure, connecting the auditory capsule to the basal plate. The fisura metotica is continuous postero‐dorsally with the fissura occipitocapsularis. The distal bent end of the shaft of the columella auris represents the processus dorsalis, and the nodule that separates from it and fuses with the quadrate is the intercalare. The interorbital septum, orbitosphenoid cartilages, basitrabecular processes and planum supraseptale are completely absent. The concha nasalis is of the simplified type, the active factor in its formation is the folding of the olfactory epithelium. The solum nasi is greatly reduced and comprises the floor of the cupola anterior, the composite lamina transversalis anterior, cartilago ectochoanalis, cartilago hypochoanalis and ectochonal plate. The branchial arches are completely absent. The pterygoquadrate is represented only by the quadrate cartilage. The ceratohyals are extremely long.

Full Text
Paper version not known

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

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.