A KEY TO THE GENERA AND THE SPECIES OF THE 



DESMIDIE^.* 



Plants composed of symmetrical cells, usually constricted in the 

 middle, often of beautiful, ornamental forms, single or conjoined 

 into filiform series, and sometimes involved in a maternal jelly. 

 Asexual multiplication takes place by transverse division, or by sep- 

 aration of the semi-cells, and by development of new parts similar to 

 the mother semi-cells.** 



*The greater part of the following key was originally published in ' 'The American 

 Monthly Microscopical Journal," and is here reproduced by permission of the editor. 

 **Wolle: Desmids of the United States. 



