Myxophyceae 1 1 



Plate I. fig. 10. 



Submerged; plants 5-6 mic. in diameter, single or in pairs; cell walls 

 hyaline, very thin; cell contents pale blue-green. 



California. On the outside of a dripping water tank. Berkeley. April 

 1904. (Gardner). 



Genus SYNECHOCOCCUS Naegeli. 

 Gatt. Einz. Alg. 56. pi. i. 1849. 



Plants oblong, cylindrical or ellipsoidal, usually single, occasionally 

 forming families of two or four united in a row or chain; sheaths none; 

 cell walls thin; cell contents blue-green, sometimes yellowish, pinkish or 

 pale orange; reproduction by division of the cells in one direction only. 

 I Cell contents blue-green. 



1 Cells 7-15 mic. in diameter, 14-26 mic. in length S. aeruginosas 



2 Cells 2 mic. in diameter, 4-6 mic. in length S. racemosus 



3 Growing in hot salt water; cells 3 mic. in diameter, 6 mic. in length 



S. curtus 



20. Synechococcus aeruginosus Naegeli. Gatt. Einz. Alg. 56. pi. i E. f. i. 



1849. De Toni. Syll. Algar. 5:27. 1907. 

 Farlow. Notes on the Cryptogamic Flora of the. White Mountains. 

 Appalachia. 3:236. 1883. Tilden. Am. Alg. Cent. II. no. 195. 1896; On 

 some Algal Stalactites of the Yellowstone National Park. Bot. Gaz. 24: 

 198. pi. 8. f. 6. 1897. Observations on some West American Thermal Al- 

 gae. Bot. Gaz. 25: 103. 1898. Collins. Algae of the Flume. Rhodora. 6: 

 230. 1904. 



Plate I. fig. II. 



Plants 7-IS mic. in diameter, 14-26 mic. in length, oblong or somewhat 

 cylindrical, obtusely rotund at both ends, single or in pairs; cell contents 

 homogeneous, light or pale blue-green. 



Greenland. (Boergesen). New Hampshire. Moist rocks at the 

 Flume. Lake Willoughby. (Farlow). Wyoming. One of the three 

 species of Blue-green algae which formed algal "stalactites." Growing in 

 a small cave made by the cone of a geyser. Valley of the Nez Perces 

 Creek. Lower Geyser Basin. Yellowstone National Park. June 1896. (Til- 

 den). 



21. Synechococcus racemosus Wolle. Fresh-Water Algae. V. Bull. Torr. 



Bot. Club. 8:37. 1881. De Toni. Syll. Algar. 5:28. 1907. 



Plant mass amorphous, blue-green; plants 2 mic. in diameter, two to 

 four times longer than broad, oblong-cylindrical, with rounded ends, often 

 showing a regular vertical arrangement, densely aggregated; cell contents 

 homogeneous, pale blue-green. 



Pennsylvania. Glass sides of aquarium. Bethlehem. (Wolle). 



22. Synechococcus curtus Setchell in Collins, Holden and Setchell. Phyc. 



Bor.-Am. Fasc. 28. no. 1351. 1907. 



