6. A NEW GENUS OF BLUEGREEN ALGAE. 



Frederic E. Clements 



and 



H. LeRoy Shantz. 



In studying the algae collected during an ecological investigation 

 or Seven Lakes, a group of alpine lakes just south of Pikes Peak, 

 Dr. Shantz found a form which could not be referred to any known 

 species. The plant was submitted to Dr. Clements, who recognized 

 it as a new genus closely related to Merismopedia. This ready recog- 

 nition arose from the fact that he had frequently stated to his ad- 

 vanced classes that there must be in existence somewhere a form 

 resembling Sarcina but bluegreen in color. Material was sent later 

 to Dr. G. T. Moore and to Dr. W. A. Setchell, both of whom stated 

 that in all probability the plant was new. The plant was first col- 

 lected in a pond on Bald Mountain, the peak just south of Pikes 

 Peak, during August and September, 1903. It was found in the 

 same pond again in August and September, 1904 and 1905. The 

 collection of September 17, 1904 was richest in this form, but the 

 colonies were rare even in this material. The pond is a shallow one, 

 lying at an altitude of nearly 12,000 feet. It is fed by rills from 

 the snowbanks on the mountain slopes which encircle it, and in the 

 short summer by springs. The pond is often frozen over until late 

 in June, and freezes again in October. During the summer of 1904, 

 when the colonies were more frequent than usual, the temperature 

 of the water never exceeded 13 degrees C. Collections were made 

 repeatedly in the neighboring lakes, Seven Lakes, Dead Lake and 

 Lake Moraine, without finding the plant in any of them. This makes 

 it probable that the plant is endemic in the original pond, an assump- 

 tion borne out by the fact that the pond is in the bottom of a moun- 

 tain-girt valley, with only an abrupt and narrow outlet downward 

 into the forested subalpine region. 



The single cell is identical with that of Chroococcns, and the real 

 nature of the plant does not become evidently different until the 



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