Figure 6.

Stage of metanephridial system development in Lepidochitona corrugata with individual components differentiated (spm 7).A. Posterior part of specimen from dorsal with transparent external surface and plane (ortho slice) of section images shown in B–D. B. Total LM cross section through the anlagen of the metanephridial system with stippled rectangle indicating the position of details given in the TEM sections C, D. C. Left anlage of renopericardial duct (dorsal) and kidney (ventral) showing the connection of the lumen of the renopericardial duct with that of the anlage of pericardium and heart. Stippled rectangle indicating the position of the TEM section D. D. Lumen of the anlage of the kidney. aj, adhaerens junction; ci, cilia; dgl, digestive gland; ec, epidermal cell; f, foot; i, intestine; lap, lumen of the anlage of pericardium and heart; lln, left lateral nerve cord; mc, mitotic cell; mu, muscle fibers; nu, nucleus; rak, right anlage of renopericardial duct and kidney; r, rectum; rln, right lateral nerve cord; va, vacuole.