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Children aged 3 and 4 were asked to name from memory items belonging in a house. Experimental groups completed the task twice, under two conditions. In the function-context condition, the experimenter provided a verbal description of use in response to each item named. In the objectcontext condition, the child was given a miniature replica of each item named. A control group at each age received only general encouragement for each response. Results indicated that the function context was more facilitative to retrieval than was the object context, which did not differ in effect from the control condition. Function context also had major effects on the types of items retrieved: More room items and fewer people and animals were produced in the functioncontext condition than in the other conditions. The representation of function and action in early conceptual schemes is discussed.

Although numerous, small, manganese oxide deposits associated with dolomite in the Eastern Transvaal escarpment, Republic of South Africa, have been known for many years, their mineralogical make-up is somewhat controversial. Chemical, mineralogical, and morphological properties of the weathering products of dolomite and the coexisting manganese oxide material in the Graskop area were therefore determined. Mn and Fe occur only in minor accessory minerals in the original rock; however, in the weathering residue, these elements are concentrated and occur as separate mineral phases, chiefly birnessite, nsutite, and goethite. Thin veins of pure muscovite and quartz traverse the residua. Rare, pure calcite and maghemite nodules were noted throughout the residual manganese material. The properties of this weathering sequence suggest that the manganese wad deposits were formed in situ as a result of the congruent dissolution of dolomite, leaving a porous, sponge-like structure, highly enriched in Mn and Fe oxides.