1885.] 



MICROSCOPICAL JOURNAL. 



223 



tion of ProtococcJis nivalis^ but 

 that, being tenacious of life, it pre- 

 serves its vitality when cast upon so 

 chilling a surface, and under favora- 

 ble circumstances even propagates 

 its species Having be- 

 come once established in the snow, it 

 is possible that, by the intense cold 

 of winter, the vegetating power may 

 be suspended beneath the frozen sur- 

 face, when, in other situations, it 

 would have perished ; and thus, on the 

 annual dissolution of the superincum- 

 bent snow, our Protococcus^ numer- 

 ous as the grains of sand on the sea- 

 shore, may start at once into renewed 

 life, and seem indeed to have de- 

 scended unseen from the clouds.' 



I was led to review the literature 

 of the red snow for the purpose of 

 discovering some basis upon which its 

 systematic position among the algae 

 could be established, but so little has 

 been written about the life-history of 

 the plant that it is impossible to as- 

 sign it to any genus. The observa- 

 tions of Bauer seem to me very un- 

 satisfactory. Agardh did not observe 

 its method of propagation, but es- 

 tablished the genus Protococcus upon 

 the characters observed by him — 

 globules aggregated, without mucous. 

 This generic character does not hold 

 even for this plant, as Greville ob- 

 served, and this author, deeming the 

 plant generically distinct from others 

 then known, adopted Agardh's name 

 Protococcus^ but characterized the 

 genus as follows : — ' Globules aggre- 

 gated, naked, containing granules, 

 sessile upon a transparent gelatinous 

 mass.' Greville, as already men- 

 tioned, observed and figured granules 

 which escape by rupture of the pa- 

 rent cell. It may be presumed that 

 these small red or yellowish granules 

 are young cells of succeeding genera- 

 tions, but their growth has not been 

 observed. Baron Wrangel, who re- 

 garded the plant a lichen, to which 

 he gave the name Lepraria ker- 

 mesina^ placed some limestone cov- 

 ered with the plant in water, and ob- 

 served a number of globules of a 



yellowish color of which the larger 

 red ones seemed to be composed. He 

 also observed the large globules swim 

 about, like infusoria, burst, and give 

 exit to smaller ones. Dr. Hooker, 

 with excellent reason, it seems to me, 

 regarded the plant as a Pabnella. 



In the latest literature of algoe the 

 plant is classed as a Chlamvdococcus^ 

 and it is this that first led me to 

 search the literature for some facts to 

 justify such a classification. It seems 

 to be based entirely upon the fact that 

 Agardh's genus Protococcus is now 

 merged into Chlamydococcus. Until 

 the method of propagation of this 

 plant is more satisfactorily established, 

 it is impossible to fix its systematic 

 position. I consider the assumption 

 that the red snow is identical with the 

 Protococcus pluvialis described by 

 Cohn, is not supported by sufficient 

 knowledge. 



The bright red color of this plant 

 may or may not be of special signifi- 

 cance in classification. It is not im- 

 probable that in its actively vegetating 

 condition the plant is green. This 

 is indicated by the observations of 

 early discoverers. Such a change of 

 color is not unusual among certain 

 algae. It is a characteristic of many 

 unicellular forms, especially Chlamy- 

 dococcus and Chlamydomo7tas . The 

 change from green to red is of great 

 physiological importance in these 

 instances. 



A specimen of the red snow col- 

 lected by Dr. Kane from the crimson 

 cliffs of Beverly is in the National 

 Museum, designated on the museum 

 register No. 10,119. This specimen 

 was recently brought to my notice by 

 Mr. A. H. Clark. It was in a glass- 

 stoppered one-ounce wide-mouth bot- 

 tle. The material was evidently put 

 in with water, but is now thoroughly 

 dry. The stopper could not be re- 

 moved without breaking the bottle, 

 hence I have transferred the contents 

 to another bottle, which is before you. 



On examination I find abundance 

 of the cells of red snow in this collec- 

 tion, but the brilliant crimson color is 



