Abstract: Wilberts protatgol method was used in the study of morphology and morphogenesis of Aspidisca pulcherrima Kahl,1932 during its asexual reproducing cycle.The process is:1)After appearance of the oral primordium (OP),first 3,then 5 thin streaks of cirral anlagen are formed anterior to TC.2)The kinetosomes within OP assembly into neatly arranged membranelles and thus the new AZM is formed,which is divided later into two parts:A-AZM and B-AZM.3)The new paroral membrane derived from posterior end of OP while the "buccal cirrus"is formed from the OP-field (as a pouch beneath the cortex).4)Cirral anlagen generate 8 frontoventral and 5 transverse cirri.5)In dorsal bristle rows,the 1st-4th new anlage of both proter and opisthe develops in the middle part of the anterior and opsterior half of each corresponding bristle row.Each primordia extends forward and backward,taking the place of old structure.