. Bulletin of the British Museum (Natural History) Geology Supplement. 46 UPPER CRETACEOUS TELEOSTS enp t. sop Fig. 20. Cimolichthys levesiensis Leidy. Hyopalatine and opercular bones and mandible of the right side in medial view. From the head becoming lower and finally terminating near the ventral end of the bone. The preoperculum lies against the posterior face of this crest and is overlapped slightly by it. The hyomandibular tapers ventrally and its anterior extent is thin and covered laterally by the metapterygoid. The hyomandibular branch of the facial nerve entered the
. Bulletin of the British Museum (Natural History) Geology Supplement. 46 UPPER CRETACEOUS TELEOSTS enp t. sop Fig. 20. Cimolichthys levesiensis Leidy. Hyopalatine and opercular bones and mandible of the right side in medial view. From the head becoming lower and finally terminating near the ventral end of the bone. The preoperculum lies against the posterior face of this crest and is overlapped slightly by it. The hyomandibular tapers ventrally and its anterior extent is thin and covered laterally by the metapterygoid. The hyomandibular branch of the facial nerve entered the bone through a large foramen in the antero-dorsal region of the medial face immediately posterior to the anterior hyomandibular head. The nerve passed within the bone following a course parallel with that of the crest on the lateral face, and divided to give rise to the three main branches of the hyomandibular nerve. The opercular nerve left through a foramen above the opercular condyle in the angle between the main body of the hyomandibular and the lateral crest. The mandibular nerve passed through a foramen below the opercular condyle and here the posterior edge of the hyomandibular is excavated slightly. The mandibular nerve continued ventrally along a groove in the posterior edge of the hyomandibular. The hyoidean nerve may have left in the same region as the mandibular nerve since there is a second smaller foramen below the condyle. On the internal face of the quadrate a short stout bone is inclined forwards ven- trally and is slightly mesially constricted. This bone by its position suggests a symplectic, but in shape it resembles an interhyal. The quadrate is triangular with a prominent transverse condyle. The groove which housed the symplectic ends ventrally above the condylar region. The post- erior edge of the quadrate is slightly thickened and lies against the thickened edge of the lower part of the preoperculum. Anteriorly the quadrate overlaps, laterally, the poster
Size: 2124px × 1177px
Photo credit: © Book Worm / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookauthorbritishmuseumnaturalhistory, bookcentury1900, bookcoll
