[Morphology and development of the cranium of Felis silvestris f. catus Linné 1758--a contribution to the comparative anatomy of the Carnivora. III: Ear region and occipital region].
In Felis, the otic region of younger embryonic stages up to Felis 1 is characterized by extremely medial extended cochleae, compressing the basal plate to a slender trabeculum. As a result of a quite strong rostrad convergence of the long axis of the ear capsules, the Commissura praefacialis fuses with the Commissura orbitoparietalis laterally. Until now, this has been found in whales only. Continuing embryogenesis towards Felis 2, the cochlea moves laterally and slightly ventrally, so the angle of convergence between the whole Capsula otica and the skull base decreases. The problem of interpreting these positional changes of the Capsula otica during phylogenesis and ontogenesis is discussed in detail. Up to recent literature, there is a discussion about homology of the Foramen perilymphaticum and allied structures in reptiles referring to the openings in the Capsula otica in mammals. Configuration of these structures in fissiped carnivores and the appearance of a "limitating membrane" in Felis 2, gives reason for a new discussion of these problems. Composition of the Bulla tympani is a very important feature for investigation of phylogeny and systematics in fissiped carnivores. In Felis 2, there appears a caudal entotympanic, consisting of young cartilaginous tissue. The development of the caudal entotympanic has impact on 2 structures in the occipital region: The Lamina alaris and the Processus paracondyloideus. Felis 1 shows a distinct Lamina alaris and a short Processus paracondyloideus. With Felis 2, either element is reduced largely, probably to the extent as the caudal entotympanic develops.
Timm
S
S
Zoologischen Institut und Zoologischen Museum, Universität Hamburg, BRD.
D000818:Animals; D005075:Biological Evolution; D002415:Cats / Q000033:anatomy & histology*; D004423:Ear / Q000033:anatomy & histology*; D004432:Ear, Middle / Q000033:anatomy & histology; D009777:Occipital Bone / Q000033:anatomy & histology*; D010802:Phylogeny; D012886:Skull / Q000033:anatomy & histology
Zur Morphologie und Entwicklung des Craniums von Felis silvestris f. catus Linné 1758--ein Beitrag zur vergleichenden Anatomie der Carnivora. Teil III: Regio otica and Regio occipitalis.