III. 



NOTES OX THE CHARACEiE, WITH A LIST OF SPECIES FE0:M 

 THE SOUTH MIDLANDS. 



By James Saunders. 

 Read at Watford, 2\st January, 1896. 



General Appearance and Mode of Occurrence. 



The plants known as the Cliaracece or Stoneworts are an entirely 

 aquatic gronp, livinc: in pools, canals, lakes, and quiet rivers, as 

 well as less frequently in rapid streams. The English name "stone- 

 TTort " is applied on account of the amount of lime which is secreted 

 in the tissues of some of their genera. When growing they are 

 always submerged, and if exposed to the air they rapidly die. 

 Some are so sensitive to dry air that I have often found it ex- 

 pedient to put my specimens under pressure at the moment of 

 gathering, a precaution the neglect of which I have frequently 

 had to regret. 



The stoneworts vary in colour from a dark green to a greyish 

 green, and, when growing in clear water, they may usually be 

 recognized by their denseness and rigid habit. In quiet and deep 

 pools they grow erect or nearly so ; in shallow brooks they are 

 prostrate, and in these situations they are sometimes grey and very 

 brittle from the incrustation of lime. 



Some of the species, especially those of the genus Chara, have 

 a peculiar fetid odour which is very noticeable when the plants 

 are exposed to the effects of drought. They are sometimes so 

 malodorous that their presence may be detected by the organs of 

 smell when one is passing near them. This is most perceptible 

 in the evening, and I have sometimes been thus apprised of their 

 presence when it has been too dark to see them. 



The foliage is reduced to branch-like organs. The whole of the 

 plant above the roots is green, and hence can assimilate. As this 

 function is so widely distributed in the individual, gi-owth is rapid. 

 Sometimes they occupy nearly the whole of the space in a recently- 

 made pool, especially in clay- or marl -pits. In this respect they 

 may be styled "the pioneers of aquatic vegetation," to quote from 

 a paper by Messrs. H. and J. Groves. In their decay they produce 

 soil in which other forms of vegetation speedily grow. 



They are singularly independent of their roots, which are small, 

 and serve mainly for attachment. As they can flourish in situations 

 devoid of vegetable soil, it is evident that they grow upon the 

 carbon-dioxide contained in the water, their tissues being permeable 

 to the fluid in which they live. So little do they depend upon 

 their roots for sustenance that we had plants under cultivation for 

 a year which were devoid of those organs, they having been broken 

 off in obtaining the specimens. 



It is note worthy that until the last 15 or 20 years the C'haraceee 



