Raphides in the Uncalcified Siphonous Green Seaweed, Codium minus (Schmidt) P. C. Silva

Figure 1

Calcium oxalate needles and bundles of needles in Codium minus: (A) C. minus; (B) utricle with needle bundles and individual needles (arrows). (C) SEM of individual needles. (D) Individual needles and a needle bundle, the latter contained within a matrix or membrane (arrow); (E) and (F) TEM of needle tips showing twisting of crystal (E, brackets) and an apparent membrane about individual needles (arrows); (G). Needle bundle staining intensely for calcium oxalate (Yasue [22]). Scale bars: (A) ruler in mm; (B) 100 μm; (C) and (D) 20 μm; (E) and (F) 0.5 μm; (G) 50 μm.