论弓石燕科的腹窗板

来源期刊：中南大学学报(自然科学版)1979年第3期

论文作者：区元任

文章页码：12 - 15

关键词：石燕科； 腕足动物化石； 窗孔； 三角双板； 假窗板； 珊瑚个体； 贝壳； 寄生； 病理性； 壳宽

摘    要：腕足动物营海生底栖生活，通常以肉茎固着海底或其他物体。肉茎从腹壳内经腹窗孔伸出，肉茎萎缩或消失后，窗孔可被腹窗板(Deltidium)覆盖。

Abstract: In this paper, the writer describes a new sub-type of deltidial plates about the family Cyrtospiriferidae. These plates differ from xenidium by their layers growing medially from margins of of delthyrium, and differ from deltidial plates by their imbricate structure and. convex shape. A new term, imbricate deltidial plates, are suggested here. We are convinced that the modification dealing with the delthyrium of the, family Cyrtospiriferidae should be emended as either closed by prominent convex xenidium or imbricate deltidial plates, although it remains open generally. The shells of Devenian spiriferoids are usully attached by Aulopora.These auloporids might oppress the valves growing asymmetry. Mistakes are easily made when we identify specimens uncarefully.