Artifact collections made as part of surveys conducted in northern San Diego County during the late 1940s and early 1950s included hammer-like implements characterized by batter and evidence of wear. Such artifacts were typically irregular in form, seemingly lacked evidence of purposeful shaping, and for lack of a better designation, were termed hammergrinders. Some kind of undefined multi-purpose function was assumed (Warren, True, and Eudey 1961: 17). At the time such artifacts were not given a great deal of consideration, and the only real concern was that they were cultural and that their critical identifying attributes were the not always obvious wear facets on one or more surfaces.
Unfortunately, in the years since 1961, no systematic treatment of this artifact has been proposed or published, and they are seldom mentioned in regional reports. Reasons for this lack of mention and/or reporting are uncertain but several possibilities come to mind: 1. It may be the case that they are not being recognized. This is especially likely (possible) when they are made of local rock with minimal evidence of cultural modification; 2. In other cases it may be that specimens fitting this category have been recognized as artifacts and collected, but were placed in a hammerstone category without further comment; 3. In a few cases (probably rare) such artifacts were collected and categorized as incipient manos or rubbing stones; 4. It may be that people working in the larger area are actually collecting these implements and simply prefer not to use the term hammergrinder.
It is not the purpose of this paper to argue for any particular name, and it does not matter what the artifacts are called. It does matter if they are not considered in the overall assessment of the local and regional prehistory. Fig. 1 shows the location of the study region.