N° i 3 . Ditch, Col du Ruiz, Dcp. Antioquia, Central Andes. Altit. 3700 in. 
N os i 4 , i 5 and 16. Laguna de la Savane de Bogota, Dep. Gundinamarca, Eastern 
Andes. Altit. 2680-2600 m. 
N os 17, 18 and 19. Ditches near the Laguna de la Savane de Bogota, Dep. Cundi- 
namarca, Eastern Andes. Altit. 2680-2600 m. 
N° 20. Laguna Pedropalo, near Tena, Dep. Cundinamarca, Eastern Andes. Altit. 
about 2000 m. 
N° 21. Plankton-colleclion from Laguna Pedropalo, near Tena, Dep. Cundinamarca, 
Eastern Andes. Altit. about 2000 m. 
N° 22. Ditch above the slope of Tequendama, Dep. Cundinamarca. Eastern Andes. 
Altit. 2210 m. 
N» 23 . Laguna de Ubaque, Dep. Cundinamarca, Eastern Andes. Altit. 2066 m. 
N° 24. Laguna de Paramo Cruz Verde above Bogota, Dep. Cundinamarca, Eastern 
Andes. Altit. 2700 m. 
The most important previous publications on South American freshvvaler Algæ are 
those of Noiidstedt, Bôrgesen, Bouge and JVIobius on Algæ from Brazil, Bouge on Algæ 
from Bolivia, Paraguay, Uruguay and Argentina (including Patagonia), Lageuheim on the 
Algæ of Ecuador, Racibousiu on some Desmide from British (îuiana, and O. Müller on 
Diatoms from South Patagonia. Various other records of South American freshwater 
Algæ hâve also appeared in sundry publications dealing witli tropical Algæ, and quite 
a number in Wittuogk, Noiidstedt and Lagerheijm’s “ Algæ Exsiccatæ ”. 
The collections from the Columbian Andes bave yielded altogether 3 1 1 species, of 
which nearly half are Desmides, as may be seen from the following table. 
Généra Species 
Myxophyceæ 18 39 
Peridinieæ 2 4 
Bacillarieæ 16 49 
Chlorophyceæ 
Isokontœ 26 46 
Akontœ ( Conjugales ) 
Zyçjnemaceæ 3 10 
Desmidiaceœ 18 1 4 8 
Stephanokontœ 2 8 
Heterokontœ 4 7 
Total 89 3 1 r 
Of the above, 24 species (and also 1 1 varieties) are here described for the first time 
as new to science. 
As the author has mentioned in many previous publications the Desmidiaceæ is par 
excellence the family of freshwater Algæ which shows definite geographical peculiarities, 
