Process and Pattern in Cladonia Subcervicornis.
AbstractMorphogenesis of podetia inCladonia subcervicornisis a non-linear, repeating process based upon a pattern of meristem enlargement and division. Variability in mature podetia ofC. subcervicornis, which may appear branched or scyphoid, is the result of variation early in ontogeny. The growth pattern ofC. subcervicornisrepresents a continuum of developmental stages. It is impossible to predict the form of the mature thallus ofC. subcervicornisbecause growth in this species is fluid. The morphology of the mature thallus ofC. subcervicornisis difficult to circumscribe using conventionalCladoniaterminology, because the processes that form the thallus are dynamic and heterogeneous. The meristem shapes that are produced during early ontogeny inC. subcervicornisare relatively simple, and the processes by which they are formed are uncomplicated. Yet podetial form inC.subcercicornisis difficult to interpret.