Simons E V
Acta Morphol Neerl Scand. 1975 Dec;13(4):287-304.
In order to be able to describe adequately the developmental anomalies of the chondrocranium in unilateral anotia in the chick embryo, it seemed necessary to describe the essentials of the normal chondrocranial development. The following observations proved to be different from the available descriptions: 1. the occipital processes do not fuse with the ear capsules; 2. the tectum synoticum fuses only with the ear capsules; the occipital processes fuse later with the tectum synoticum by outgrowth to dorsal; 3. in the chick embryo there is no evidence for the existence of a tectum posterius; 4. the metotic fissure is in the cartilaginous stage of development not closed, but shifts laterally; 5. there is strong evidence that the pro-otic processes arise as independent structures which later fuse with the ear capsules. The results of the study of the development of the chondrocranium in the embryos in which experimentally unilateral anotia is produced, will be described in a following paper.
为了能够充分描述鸡胚单侧无耳畸形中软骨颅的发育异常，似乎有必要描述正常软骨颅发育的要点。以下观察结果与现有描述不同：1. 枕突不与耳囊融合；2. 联合顶仅与耳囊融合；枕突后来通过向背侧生长与联合顶融合；3. 在鸡胚中没有证据表明存在后顶；4. 颞骨裂在软骨发育阶段未闭合，而是向外侧移位；5. 有强有力的证据表明耳前突作为独立结构出现，后来与耳囊融合。在实验性产生单侧无耳畸形的胚胎中软骨颅发育的研究结果将在后续论文中描述。
