Coalescence of ripplons, breathers, dromions and dark solitons

New solutions of several nonlinear evolution equations (NEEs) are obtained by a special limit corresponding to a coalescence or merger of wavenumbers. This technique will yield the multiple pole solutions of NEEs if ordinary solitons are involved. This limiting process will now be applied through th e Hirota bilinear transform to other novel solutions of NEEs. For ripplons (self similar explode-decay solutions) such merger yields interacting self similar solitary waves. For breathers (pulsating waves) this coalescence gi ves rise to a pair of counterpropagating breathers. For dromions (exponenti ally decaying solutions in all spatial directions) this merger might genera te additional localized structures. For dark solitons such coalescence can lead to a pair of anti-dark (localized elevation solitary waves on a contin uous wave background) and dark solitons.