The adult grinder is formed through the sequential addition of layers, coincident to displacement and degradation of the L4 grinder.

(A) 10 minutes post-PC and (B) 15 min post-PC. (i) TEM of the terminal bulb. (ii) Pseudocoloring. Light brown denotes the terminal bulb lumen, yellow denotes the L4 pharyngeal grinder, red denotes the bottom boundary of L4 pharyngeal grinder, cyan denotes the separation space, blue denotes the upper boundary of pm6, purple denotes pm6 papillae, pink denotes pm6, and navy denoting pm7. (iii) Cartoon using the color scheme used in (ii) with the addition of plasma membranes shown in orange. Anterior is up. Scale bar = 1 μm.