Germination stages on aqua fortis

The germination stages of a sunflower (helianthus) and a bean (vicia) on aqua fortis (5% formaldehyde) in plastic containers. They were prepared by griffin biological laboratories ltd, tonbridge, england. These preparations were mainly used for educational purposes in schools. Second quarter of the 20th c. 26 x 16(11) x 4.5cm.