Flax family, Linaceae.

Kind of seed: Flax. (a) General description. (1) Germination habit: Epigeal dicot. (Due to the mucilaginous nature of the seed coat, seedlings germinated on blotters may adhere to the blotter and appear to be negatively geotropic.) (2) Food reserves: Cotyledons which expand and become photosynthetic. (3) Shoot system: The hypocotyl elongates carrying the cotyledons above the soil surface. The epicotyl usually does not show any development within the test period. (4) Root system: A primary root, with secondary roots usually developing within the test period. (b) Abnormal seedling description. (1) Cotyledons: (i) Less than half of the original cotyledon tissue remaining attached. (ii) Less than half of the original cotyledon tissue free of necrosis or decay. (2) Epicotyl: (i) Missing. (May be assumed to be present if cotyledons are intact.) (ii) [Reserved] (3) Hypocotyl: (i) Deep open cracks extending into the conducting tissue. (ii) Malformed, such as markedly shortened, curled, or thickened. (4) Root: (i) None. (ii) Weak, stubby, or missing primary root with weak secondary or adventitious roots. (5) Seedling: (i) One or more essential structures impaired as a result of decay from primary infection. (ii) Albino. [59 FR 64505 Dec. 14, 1994]