Description | Slide shows five black and white diagrammatic drawings 'illustrating the various stages in the asexual formation of a chain of zooids'. Each drawing is labelled and explained in the description which begins at the top left of the slide: 'Fig. 148 - diagrams llustrating the various stages in the asexual formation of a chain of zooids. (Modified from Malaquin). I, Heteronerid or Heterosyllid stage. A, Non-sexual; A', sexual region of the body with modified parapodia. II, Syllis. The A' hinder the sexual region. B, is similarly modified, and it will separate from the parent zooid, A, and become and independent zooid. III Autolytus. The hinder zooid B develops a head by budding before separation. IV, Autolytus etc., A zone of budding (z) makes its appearance in front of the head of B, and by its growth will give rise to a series of new segments in the middle of the body. V, Myrianida, Autolytus, etc. From this zone of budding a very large number of segements have been formed, which have further, become grouped so as to form three individuals, C, D, E; B is the hindermost zooid, which is either formed from the hinder segments of the parent zooid or is produced by budding like C, D, E.' |