README: slide-mounted not petri-dish

README.md

@@ -115,7 +115,7 @@ The PHOEBI-6 LCO held-out combinations at seed 1337 are: `bt`, `bs_pf`, `ka_fj`,
 
 ## Wet-lab protocol
 
-Cultures were inoculated from glycerol stocks into nutrient broth (8 g L⁻¹), sterilised by autoclave (121 °C, 15 min), and grown at 30 °C with orbital shaking at 250 rpm for 72–120 hours. Once each culture reached its characteristic growth stage, Petri dishes were prepared from the broth and imaged on an inverted phase-contrast microscope (100× oil-immersion, NA 1.25). For PHOEBI-6 three pairwise combinations (`bs`+`bt`, `bt`+`fj`, `ka`+`pf`) and the five-species combinations were not collected and are absent from the release.
+Cultures were inoculated from glycerol stocks into nutrient broth (8 g L⁻¹), sterilised by autoclave (121 °C, 15 min), and grown at 30 °C with orbital shaking at 250 rpm for 72–120 hours. Once each culture reached its characteristic growth stage, samples were mounted on glass slides and imaged on an inverted phase-contrast microscope (100× oil-immersion, NA 1.25). For PHOEBI-6 three pairwise combinations (`bs`+`bt`, `bt`+`fj`, `ka`+`pf`) and the five-species combinations were not collected and are absent from the release.
 
 ## Tasks supported