INVERTEBRATE ZOOLOGY - H. I. Shcherbak - 2008

KINGDOM MULTICELLULAR ANIMALS (METAZOA)

SUBKINGDOM TRUE METAZOA (EUMETAZOA)

SECTION TRIPLOBLASTIC (TRIPLOBLASTICA) OR BILATERAL (BILATERIA) ANIMALS

SUBSECTION SPIRALIA (SPIRALIA)

PHYLUM FLATWORMS (PLATHELMINTHES)

SUBPHYLUM TURBELLARIANS (TURBELLARIA), OR ARCHIDERMATA (ARCHIDERMATA)

SUPERCLASS ARCHOPHORA (ARCHOPHORA)

The most primitive turbellarians possess a statocyst (except for polyclads) and a simpler Reproductive System Structure: they lack yolk glands (vitellaria), and their eggs are simple, consisting of an oocyte surrounded by a shell capsule. In some turbellarians, development proceeds through metamorphosis.



Last update: 13/08/2026

Editorial and Educational Adaptation: This material has been compiled based on the primary/original source text. The project team performed an editorial review, corrected technical inaccuracies, structured sections, and adapted the content for an educational format.

What was processed:

  • elimination of formatting defects (OCR errors, structural breaks, corrupted characters);
  • editorial organization of content;
  • standardization of terminology in accordance with academic sources;
  • verification of factual statements against the original source text.

All mentions of the author, publication year, and origin of the primary text have been preserved in accordance with the source.