SYMPLECTIC SPHERES WITH POSITIVE ORDINARY DOUBLE POINTS AND ALGEBRAIC-CURVES IN CP2

We prove that every symplectic sphere having only positive ordinary do uble points as singularities, is symplectically isotopic to an algebra ic curve. In the same way, all generic set of imbedded symplectic sphe res of degree I which are positively transverse to one another is symp lectically isotopic to a set of complex lines. (C) Academie des Scienc es/Elsevier, Paris.