FIG. 2.

(A–C) Germination and outgrowth of B. thuringiensis subsp. israelensis spores and vegetative bacteria in excreted T. pyriformis food vacuoles (suspension 1) after 7 h (A), 15 h (B), and 20 h (C) of incubation. a, single food vacuoles; b, aggregates of excreted vacuoles; c, chains of vegetative bacteria breaking out of the aggregates; d, live T. pyriformis cells loaded with spores. Magnification, ×400. (D) Single spores in water (control suspension 2) after 20 h of incubation. Magnification, ×1,000.