124 Th e Scottish Naturalist. 



the name of Sphcerclla nivalis. It was found in Russian Lapland 

 by Middendorf on July 27th, 1840, and towards the northern ex- 

 tremity of the Ural mountains by Schrenk on the 15th of August, 

 1848. Since then it has been found on the Pyrenees and the 

 Carpathians, on Sierra Nevada, in California, and in the Antarctic 

 regions, so that it may, like so many of the algae, fairly be regarded 

 as cosmopolitan. 



In 1870, Professor Nordenskiold's expedition to Greenland 

 took place. He was accompanied by Professor Berggren. They 

 added considerably to the Snow-Flora. One of their most remark- 

 able additions is a Desmid, Ancylonema Nordenskioldii, Berg., the 

 type, as well as the only species, of a new genus of plants. It is 

 further remarkable as being found on ice only, not on snow. In 

 many places on the inland ice it was found in great abundance, 

 giving a purplish-brown colour to the ice. Other algae were mixed 

 with the fine sand called Kryokonit (ice-dust), by Nordenskiold. 

 This dust in many places forms a thin covering on the ice, and is 

 often found in considerable quantities at the bottom of the deep, 

 narrow pits, which form so peculiar a feature of the inland ice in 

 Greenland. Nordenskiold looks upon these algae, and especially 

 the little Ancylonema, as performing a very important part in the 

 ice economy. He says : " The dark mass absorbs a larger portion 

 of the sun's rays than the white ice, and produces deep holes in 

 ice, which in a great degree conduce to its melting ; " and, after 

 remarking that the Ancylonema may once have performed the 

 same office in Scandinavia, he proceeds to say : " We have 

 perhaps to thank this plant that the ice deserts which formerly 

 covered Europe and America with a coating of ice have given 

 place to shady woods and undulating fields of corn." 



Several samples of " Kryokonit " collected in S. Greenland were 

 found to contain a number of the germinating spores of Sphcerella 

 nivalis. During the winter of 1880-81, Prof. Wittrock was fortu- 

 nate enough to succeed in getting some of these spores to develop 

 themselves ; hence he looked upon them as resting spores. They 

 seem to suffer no harm from being frozen in the ice and snow 

 during the greater part of the year, or from being dried up for 

 some months by the heat of the sun. During a large portion ot 

 the year these plants are enveloped in constant darkness and 

 gloom, when the temperature sinks very low. Dr. Kjellmann, at 

 Mossel Bay, in Spitzbergen, on February 14, 1873, found the 



