. Elementary botany. Botany. ALG^ CONTliVUED: CLASSIFICATION. 171 Classification.—KjcUman dividus the Phx-oph\'(.ea:- into two orders. 369. Order Phseosporalea (Phseosporeae) including 18 families. One of the most conspicuous families is the Laminariacea-, including among others the (iiant Kelps mentioned above (Laminaria, Postelsia, Macrocystis, etc.). 370. Order Cyclosporalea (Cyclosporeae).—This includes one family, the Fucacea: with Ectocarpus, Sphacelaria, La-athesia, Fucus, Sargassum, etc. Class Rhodophyceee. 371. The red algse (Ehodophyceaej.—The larger number of the so-called red algse
. Elementary botany. Botany. ALG^ CONTliVUED: CLASSIFICATION. 171 Classification.—KjcUman dividus the Phx-oph\'(.ea:- into two orders. 369. Order Phseosporalea (Phseosporeae) including 18 families. One of the most conspicuous families is the Laminariacea-, including among others the (iiant Kelps mentioned above (Laminaria, Postelsia, Macrocystis, etc.). 370. Order Cyclosporalea (Cyclosporeae).—This includes one family, the Fucacea: with Ectocarpus, Sphacelaria, La-athesia, Fucus, Sargassum, etc. Class Rhodophyceee. 371. The red algse (Ehodophyceaej.—The larger number of the so-called red algse occur in salt water, though a few genera occur in fresh water. The plants pjossess chlorophyll, but it is usually obscured by a reddish or purpjle pigment. 372. Nemal'on.—This is one of the lower marine forms, though its thal- lus is not one of the simplest in struc- ture. The plant body consists of a slender cylindrical branched shoot, some- times very profusely branched. The central strand is rather firm, while the is composed of rather loose fila- ments. 373. Batrachospermum.—This genus occurs in fresh, water, and the species are found in slow-running water of shallow streams or ditches. There is a central slender strand which is more or less Vjranched, and on these branches are whorls of densely crowded slender branches occurring at regular intervals. The plants are usually slipper)'. Gonidia are formed on the ends of some of these branches in globose, sporangia, called monosporangia, since but a single. ... . , , . , A red alga (Nemalion). .4 spore or gomdium is developed in each, branehes. showing antheridia Other branches often terminate in long ^arpogomum o . ^ tncnogi'ne ((), to wnicn are attached. sexual (a): carpogonium or procarp io) with its slender hyaline seta^ fresh water. two spermatia {s)\ B, beginning of „„. _ _,, . , a cystocarp (o), the trichogvne (t) 374. Lemanea.—This genus also occurs still showing; C, an almost mature tric
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