Invertebrate animals represent a diversity of solutions to life's challenges. Success in a wide range of environments has been achieved by an almost bewildering range of invertebrate body forms. These body forms are reflected in the wonderful diversity of their nervous systems. Despite this apparent diversity, studies of the development of invertebrates and vertebrates are yielding common themes at the molecular level. Likewise, the phenome non of neural regeneration is based upon properties intrinsic to neurons and responses to a remarkably conserved chemical lan guage. This monograph...