Fig. 3. Regulation of cell number in planarians of different lengths. (A) In situ hybridization of clone H112.3c, showing distribution of putative chemoreceptive neurons underlying anterior margin. Nomarski DIC view. Scale bar: 100 µm. (B) Number of H112.3c-positive cells/side in organisms of different lengths. Mean number of H112.3c-positive cells (±s.d.) is indicated (for 1 mm, n=14; 2 mm, n=9; 6 mm, n=10; 8 mm, n=7).