. Algæ. Vol. I. Myxophyceæ, Peridinieæ, Bacillarieæ, Chlorophyceæ, together with a brief summary of the occurrence and distribution of freshwat4er Algæ . movementshave become feeble or sluggish. A 2 per cent, solution of cocaine is oftenuseful in causing the cilia to come to rest. They can generally be wellobserved by rapidly killing the cells bymeans of 1 per cent, osmic acid or byiodine solution. They can also be stainedby methods essentially similar to those em-ployed in staining the cilia of Bacteria,especially the tannin and carbol-fuchsinmethod, which gives good permanent pre-parations i
. Algæ. Vol. I. Myxophyceæ, Peridinieæ, Bacillarieæ, Chlorophyceæ, together with a brief summary of the occurrence and distribution of freshwat4er Algæ . movementshave become feeble or sluggish. A 2 per cent, solution of cocaine is oftenuseful in causing the cilia to come to rest. They can generally be wellobserved by rapidly killing the cells bymeans of 1 per cent, osmic acid or byiodine solution. They can also be stainedby methods essentially similar to those em-ployed in staining the cilia of Bacteria,especially the tannin and carbol-fuchsinmethod, which gives good permanent pre-parations in which the cilia are stained brightred. In the small sub-family of the Tetra-sporeae the cells are peculiar in the possessionof motionless pseudocilia/ which in ApiocystisBrauniana are sometimes very distinct andcan be plainly observed without staining. In the large group of the Conjugatse ciliado not occur. The CHROMATOPHORES (which in all theGreen AlgaB are CHLOROPLASTS) are brightgreen or sometimes yellow-green in pigments are chlorophyll and xantho-phyll, the former being as a rule greatlyin excess of the latter. With the exception. Fig. 89. Escape of the zoogonidiumin (Edogonium; A, (E. Boscii(Le. Cl.) Wittr.; B, (E. HirniiGutw. x 460. Each zoogonidiumpossesses an anterior circlet ofcilia. w. A. 130 CMorophycese of certain of the Conjugatse the Green Algae do not apparently possess a proteinpigment soluble in water such as the phycocyanin of the Myxophycese or theclosely related red pigment of the Rhodophycese. The chloroplasts may besolitary or numerous, with entire margins, or with margins so lobed and incisedas to present an almost infinite variety of form. In most families they areparietal, but the elaborate chloroplasts of the majority of Desmids, and those ofZygnema, Prasiola, etc., are axile. In some genera the parietal chloroplastsare ribbon-like or band-like, being wound spirally round the interior of thecell-wall (Spirogyra and some species of S
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