The flattened stem and clustered flowers are due to something called 'fasciation'. There are various suspected causes including genetic abnormality, hormonal imbalance, viruses, insect damage, etc. and the phenomenon is relatively common with lilies, among a few selected plants. Typically, with lilies and similar type plants (delphiniums, foxgloves and other herbaceous perennials), the fascination is not a recurring phenomenon and it is doubtful any seeds would carry this trait.

In some plants - certain conifers, cacti, fantail willows, celosia - the fasciation is stable and will appear consistently and these types of plants are actually cultivated for their unique appearance.

Fascinating fasciation.