Muenzhigraptus Zhao et Zhang的一些构造特征

应用光学显微镜及扫描电镜对Ｍｕｅｎｚｈｉｇｒａｐｔｕｓ一属的一些构造进行研究发现，在其原胎管和线管壁上均发育有纵脊，线管纵脊是原胎管纵脊向线管的延伸，纵脊的形成晚于原胎管壁及线管壁的形成。Ｍｕｅｎｚｈｉｇｒａｐｔｕｓ的副胞管呈简单管状，随着正胞管在笔石体始部呈末端孤立至笔石体末部变为直管状无孤立部分，相应地，副胞管在笔石体始部至末部绕过正胞管背缘弯曲生长逐渐转为直管状

SOME STRUCTURES AND CHARACTERS OF THE MUENZHIGRAPTUS ZHAO AND ZHANG

Among the Muenzhigraptus, the walls of prosicula are strengthened not only by the spiral threads but also by the longitudinal ridges. It is possible that longitudinal ridge occur in all epiplanktonic dendroids. Some longitudinal ridges present in the walls of nema. These longitudinal ridges are stretch of longitudinal ridges of prosicula from top of prosicula to nema. The apertural portion of bithecae is cured in the proximal part of rhabdosome, while bithecae is straight in the distal part of rhabdosome.