Pellicle architecture in Gregarina steini gamonts. A. Gamonts associated in syzygy; primite (p), satellite (s). SEM. B. Higher magnification of the junction between the posterior end of the primite deutomerite (d) and apical part of the satellite protomerite (p). SEM. C, D. Detailed views of the junction (arrow) between folded pellicles covering the primite deutomerite (def) and satellite protomerite (pef). SEM. E, F. Organisation of more and less undulated epicytic folds covering the deutomerite. SEM. G. Higher magnification of deutomerite epicytic folds (ef); grooves (g) between folds, pore-like structure (arrow). SEM. H. Organisation of the deutomerite pellicle in cross section; epicytic folds (ef), grooves with mucus (*), internal lamina (double arrowhead). TEM. I. Cross section of deutomerite epicytic folds. Note the filamentous connections (white arrows) localised between the plasma membrane (pm) and inner membrane complex (imc); 12-nm filaments (arrowhead), rippled dense structures (white arrowhead), unknown dense structure (arrow). TEM. J. The septum (arrow) and ectoplasmic network (n); deutomerite (d), epicytic folds (ef), protomerite (p). TEM. K. Golgi apparatus in deutomerite cytoplasm. TEM. L. The duct (arrow) opening outwards to the groove between epicytic folds. TEM.