https://c8.alamy.com/comp/PG2KF9/morphology-of-gymnosperms-gymnosperms-plant-morphology-cycadales-119-ii-chromosomes-and-in-one-case-13-chromosomes-in-zamia-25-nuclei-were-examined-and-all-showed-12-chromosomes-chamber-lain-46-63-found-12-chromosomes-in-the-pollen-mother-cells-of-dioon-edule-12-at-the-mitosis-which-gives-rise-to-the-ventral-canal-and-egg-nuclei-and-12-in-cells-of-the-endosperm-please-note-that-these-images-are-extracted-from-scanned-page-images-that-may-have-been-digitally-enhanced-for-readability-coloration-and-appearance-of-these-illustrations-may-not-perfectly-resemble-the-original-work-PG2KF9.jpg