It is well known that, even a simple colony in the primitive cheilostome bryozoans (such as Membraniporid and Electrid forms) is composed of two zones: a primary zone of astogenetic change and a primary zone of ontogenetic repetition. Within a colony, ontogenetic changes in morphology are recognizable along a gradient proximally from the growing margin and astogenetic changes in morphology are expressed on a gradient distally from the ancestrula. Therefore, morphological variations within a colony are usually recognizable and used often as the characters by which different taxa are distinguished from one another. The ancestrula or ancestrular group formed after metamorphosis of the larvae may be similar to the subsequently formed zooids in morphological details. Although there is controversy on the taxonomic and phylogenetic significance of the ancestrula and early astogeny of cheilostome bryozoans have been discussed, the authors try their best to address the subject on the basis of the abundant data on ancestrula and early astogeny found in about 300 species of suborders Malacostegina, Neocheilostomina (infraorders Pseudomalacostegomorpha, Cellulariomorpha and Cryptocystomorpha) and Ascophorina (infraorders Cribriomorpha, Hippothoomotpha, Umbonulomorpha and Lepraliomorpha), and attemp to reveal their morphological series in order to extract some information about the mode of evolution supportive of the phylolenetic development of Cheilostome Bryozoans. This paper is a theses on the subject 《Significance of Early Astogeny of Cheilostome Bryozoans in their Evolution》, deals with the early astogeny of suborder Malacostegina (Families Membraniporidae and Flustridae), and includes descriptions of a new genus and six new species.