FRESHWATER ALGÆ FROM CAUCASUS AND TURKESTAN. 131 



Systematic Account. 

 Class MyiLopliycese. 



Order Coccogoneæ. 

 Family Chroococcaceæ.^ 

 Genus Chroococcus iNäg. 



1. Chroococcus cohœrens (Bréb.) Näg. 

 Rabh. exsicc. No. 446. 



Elborus; diam. cell. 3 — 5 a. 



2. Chroococcus minor (Kiitz.) Näg. 

 Rabh. exsicc. No. 1143. 



Wladikaokas — Kasbek; diam. cell. 2,5 — 3,5 ^u. 



3. Chroococcus turgidus (Kutz.) Näg. 

 Kasbek -Mleti; Tiflis. 



4. Chroococcus minutus (Kiitz.) Näg. 

 Rabh. exsicc. No. 1214. 



Kasbek — Mleti; diam. cell. 8/t; Tiflis; diam. cell. 6-10/f. 



5. Chroococcus pallidus Näg. 

 Wittr. & Nordst. exsicc. No. 400. 

 Wladikaokas — Kasbek. 



Genus Microcystis Kiitz. 



6. Microcystis sp. 

 Only one specimen. 

 Askabad. 



7. Microcystis parasitica Kiitz. 

 Kasbek —Mleti; diam. cell. ^ /.i. 



Between the filaments of Tolypothrix. Abundant. 

 Genus Merismopedia Meyen. 



8. Merismopedia glauca (Ehrbg.) Näg. 

 Askabad. 



1 For the determination of this group of a]gæ I have used the original 

 drawings and descriptions by professor Wille for a monograph of the 

 Chroococcaceæ. The note under the name of the species indicates 

 that prof. Wille has drawn his figures from that exsiccate. 



