How large is a cycad egg compared with other plant eggs?

Cycad eggs are the largest known in the plant kingdom, measuring approximately three millimetres in length.1

In contrast, the female gametophytes of angiosperms—often referred to as the embryo sac—are significantly smaller and simpler, typically containing only a few nuclei. While cycads possess a large, multicellular female gametophyte that develops archegonia to house these massive eggs, angiosperms lack archegonia entirely and utilize a much more reduced structure for sexual reproduction.213