Abstract
Internal structure of calcified tube walls of 12 species of Serpulidae and 2 species of Spirorbidae (Polychaeta) were studied using scanning electron microscope. Inner surface of tubes was smooth. The vertical structure of tube walls of six serpulid species was porous. Circular pores and meander slender pores were observed. Tube walls comprised orderly arranged prismatic-like crystals of 1.3-10.0μm long by 0.2-1.8μm wide.
