The composition of 11 natural language categories (animals, clothes, colors, flowers, fruit, furniture, insects, toies, vegetables, jobs, vehicles) in recall from long-term semantic memory at 2 ages (6 and 8 years) was analysed. Considerable variation among the categories in size and composition was found in this study. The average number of responses in each category was extremely variable, from 3.136 for furniture to 10.83 for animals. There was significant difference between two age groups. The size difference is related to the increasing articulation and hierarchization of categories by lice older children.