MaleProcFIG 5: The B lineage contributes to proctodeum development.

A&B. Lineages show contributions of the B lineage to the formation of the proctodeum. **α vs β and γ vs δ fates determined by positional cues. Spicule lineage branches are not shown. (Based on Sulston et al., 1980; Chamberlin and Sternberg, 1994; Jiang and Sternberg, 1999.)
C. Diagram showing specification of proctodeum precursor fates by cell-cell interactions. α, γ and ε are anterior fates; β, γ and ζ are posterior fates of B.a progeny. (Adapted from Chamberlin and Sternberg, 1994.)