BRITISH 

 FRESHWATER ALG^E, 



EXPLANATION OF THE PLATES. 



PLATE I. 



Fig. 1. Conferva rivularis. Spores killed by opium (magni- 

 fied 340 times). Fig. 2. Conf. glomerata. Spores killed 

 by iodine (magnified 500 times). Fig. 3. The same treated 

 with iodine and dried between two plates of glass (magni- 

 fied to the same extent). Fig. 4. The same beginning to 

 germinate (430 times). Fig. 5. Germination more advanced 

 (290 times). Fig. 6. Germination still more advanced. 

 Fig. 7. Chcetophora? Spores killed by iodine. (This and 

 the following are magnified 340 times). Fig. 8. The same, 

 treated with iodine. Fig. 9. Germination. Fig. 10. Cha- 

 tophora elegans var. pisiformis. Spores killed by iodine. 

 Fig. 11. Germination. Fig. 12. Prolif era rivularis. Spores 

 the ciliae of which are invisible by reason of the rapid 

 movement. (This and the following figures are magnified 

 341 times.) Fig. 13. The same, killed with iodine. Fig. 14. 

 The same, treated with iodine, and dried between two plates 

 of glass. Fig. 15. Germination. Figs. 16, 17. Germination 

 more advanced. Fig. 18. Prolifera Candollii. Spores killed 

 with weak iodine. Fig. 19. Germination. 



PLATE II. 



Shows the reproduction of Vaucheria clavata. Fig. 20. The 

 extremity of one of the filaments previous to the conde^- 

 sation of the contained endochrome. Fig. 21. The same, 



A 3 



