“…383-384;Hopwood, 1999Hopwood, , 2000Hopwood, , 2002Hopwood, , 2012; those techniques required an unbroken series of sections of consistent thickness. His addressed these problems by developing a protocol for the infiltration-embedding of embryos with paraffin wax (van der Lem et al, 2021). Edwin Klebs had introduced paraffin wax to histology (Klebs, 1867) but soon abandoned it (Klebs, 1869, pp.…”