This fiber ends...is an enlargement which may be rounded and subtle,but that may also adopt a conical appearance.This latter we shall name the growth cone,that at times displays fine and short extensions... ...I believe that one could also think of the migration of growth cones like the phenomenon called Pfeffer's chemotaxis......The processes of the neuroblasts become oriented by chemical stimulation,and move toward the secretion products of certain cells. Ramon y Cajal (1898)Ramon y Cajal (1898) This fiber ends … is an enlargement which may be rounded and subtle, but that may also adopt a conical appearance. This latter we shall name the growth cone, that at times displays fine and short extensions… ….I believe that one could also think of the migration of growth cones like the phenomenon called Pfeffer's chemotaxis...... The processes of the neuroblasts become oriented by chemical stimulation, and move toward the secretion products of certain cells