Contemporary Standard Spanish exhibits fourteen verbs with a segment realized as g occurring in the first person singular present indicative and throughout the subjunctive, but absent in other forms of the conjugational unit. These verbs include:' decir 'say,' hacer 'do,' and yacer 'lie,'2 which inherited g; as well as: asir 'seize,' caer 'fall,' oir 'listen,' poner 'put,' raer 'scrape,' roer 'gnaw,' salir 'leave,' tener 'have,' traer 'drag,' valer 'be worth,' and venir 'come,'" to which it has been extended.4 Thus, taking hacer as an example, we find 1sg. hago in the present indicative, and 1sg. haga, 2sg. hagas, etc. in the present subjunctive, but forms without g elsewhere; e.g., 2sg. haces, 3sg. hace, etc. in the present indicative; 1sg. hice, 2sg. hiciste, etc. in the preterit; 1sg. hacia, 2sg. hacias, etc. in the imperfect. There are at least four issues relevant in the analysis of this segment: 1. its morphological status, 2. the reason for its extension, 3. the shared attribute of verbs to which it has been extended, and 4. the nature of the extension vis-A-vis the grammar. Of these, only the first has been given adequate attention," although there has been no attempt to view it in the context of an evolving system. The remaining issues have been dealt with only briefly, with casual references to analogy, but with no attempt to be explicit." The purpose of this paper is to address these issues in the context of an integrated discussion of the structure and evolution of the verbs in question.