During the last decade research on neural transplantation in mammals has grown extensively, and has attracted the attention of many young inquisitive scientists. This growth, as the critics point out, has been somewhat random, and has resulted neither in the formulation of basic concepts nor in any other significant achievement. For instance, they question-how is it possible to jump into functional research with clinical bearing when the basic morphological work has not yet been conducted? The criticism, objectively speaking, is valid and is supported by the fact that every investigator who...