- Blue markers: specimen records
- Yellow marker: type locality, if present
- Red markers: endpoints of range from literature
Weeksia Setchell 1901
Blades large, membranous, entire, dissected, or lobed, with smooth or puckered surface, or puckered basally only; at first uniaxial, then multiaxial. Medulla of stout, periclinally directed filaments, with occasional anticlinal filaments and giant cells in longitudinal rows representing primary axial filaments; rows contributing to veinlike thickenings frequent at base of blades. Cortex of 3-5(7) layers of rounded cells, the innermost layers becoming enlarged on connecting with medullary filaments. Tetrasporangia small, inconspicuous, cruciately to irregularly cruciately divided. Spermatangia in superficial patches. Carpogonial and auxiliary-cell branches of 8-15 cells, 4 or 5 of those in carpogonial branch very conspicuous nutritive cells. Gonimoblast formed from nutritive cell, all cells becoming carposporangia, lying beneath a carpostome.
Weeksia reticulata Setch. Setchell 1901: 128; Smith 1944: 206; Abbott 1968: 190.
Thalli 10-20 cm tall, growing in cabbagelike clusters, usually with fleshy peglike holdfasts, little or no stipe, bluish-purple; blades reniform to rounded, with basally prominent veins, or the veins running longitudinally throughout blades, nearly to margins; blades remaining simple and expanded, or occasionally cleft and appearing branched; medulla of stout periclinally and anticlinally directed filaments with dense contents; cortex of 4-6 layers of pigmented cells; plants monoecious; spermatangia in small, discontinuous, superficial patches; tetrasporangia inconspicuous, within outer cortical layers, cruciately to irregularly cruciately divided; carpogonial branches and auxiliary-cell branches borne on innermost cortical cells, 8-15 cells each, frequently with short, sterile laterals on lower cells; upper 5-7 cells of carpogonial branches highly modified by dumbbell-shaped nutritive cells; carpogonium after fertilization fusing directly with 1 of these cells to form gonimoblast, all cells of which become carposporangia, these lying beneath carpostome.
Excerpt from Abbott, I. A., & Hollenberg, G. J. (1976). Marine algae of California. Stanford University Press, Stanford, California. xii [xiii] + 827 pp., 701 figs.
