122 THE FLORA OF NEBRASKA. 



Plate XXIV., Fig. 1, a portion of the plant body x50; Fig. 2, r branchlet 

 x500; Fig. 3, branchlet with antherids; Fig 4, branchlet with young car- 

 pogone; Fig. 5, carpogone with antherozoids (corpuscula) attached. The 

 carpospores have developed and cells from below have started to grow up 

 around them, thus forming a sporocarp. (Figs. 3-5 after Bornet and 

 Thuret.) 



2. CHANTR ANSIA Desv. Obs. PI. des. Env. d' Angers. 1818. 



Plants growing in tufts, bluish-green or violet, filaments irregularly branched, 

 composed of a single series of cylindrical cells, not corticated; anthe- 

 rids one-celled, on the ends of short, clustered branches; carpogones at 

 the ends of similar branches. 



Etymology: dedicated to Chantrans. 



This genus is of doubtful position. It may be placed in any one of several 

 of the lower families of the Florideae. Many of the fresh-water species 

 have been shown to be early stages of plants belonging to other well de- 

 fined genera, as Batracliospermum, Lemanea, etc. 



< 'lui ill ransia violacea Kuetz. Phyc. Germ. 231. 1845. 



Plants 1-2 mm. long, arising from a thalloid mass of cells; filaments not 



greatly branched; cells 8-10 fi wide, 5-8 times as long as broad; branches 



fastigiate; fruit on short, cylindrical branchlets. 

 Bellevue, with Batracliospermum gelatinosum. 

 PI. XXIII., Fig. 4, a portion of thallus with filaments arising. A and B 



fruiting branches. 



Class VII.-CHAROPHYCEAE. 



Slender, submerged, aquatic plants, from a centimeter to a meter long, with mono- 

 podial racemose branching and verticillate leaves; stems rising in tufts or mats from the 

 substratum to which they are fastened by slender rhizoids; sexual reproduction by means 

 of carpogones and antherids, produced monoeciously or dioeciously in the axils or at 

 the nodes of the leaves; asaxual reproduction by means of stunted branches. 



These plants are rich in chlorophyll, though this is sometimes masked by a thin coat- 

 ing of carbonate of lime, giving them an ashy-green appearance and making them very 

 fragile. 



The stems and branches are made up of a single row of long, cylindrical cells placed 

 end to end. The leaves arising from the nodes are of the same structure. Around the 

 axes there may be developed a coating of long tubular cells (cortication) parallel to the 

 axial cell. The sexual organs consist of more or less globular carpogones and antherids, 

 produced monoeciously or dioeciously in the axils, or at the nodes of the leaves. Each 

 carpogone consists of a single, large, spirally corticated cell which after fertilization 

 becomes a carpospore. The globular antherid is made up of eight "shields," within 

 which is ultimately produced on each shield a tuft of filaments, each cell of which pro- 

 duces a spirally coiled, biciliate antherozoid. 



The carpospore in germination produces a simple plant, the so-called pro-embryo> 

 consisting of a single row of cells with limited apical growth. The sexual plant arises 

 from this as a lateral branch. 



The close relation of the Bangiaceae among the lower Florideae with the Oedogon- 

 iaceae and the Coleochaeteae has already been remarked. There is no essential point in 

 the reproduction of the Charophycae or in the structure of their plant-body that differs 



