September 12, 1918] 



NATURE 



B ICTERIA OF ICE AND SNOW l\ 

 ANTARCTICA. 



THE researches we were able to prosecute during 

 Sir Douglas Mawson's Australasian Antarctic 

 lition (1911 141 in the subject of bacterial Mora of 

 snow and ice have given rise to certain queries which, 

 if accurately answered and correlated to the work of 

 four previous observers, should go far towards an 

 elucidation ol th< ologj of Antarctica as a 



a hole. 

 I )i investigations for nearly two 



..I the soil of Snow Hill Island, mar Graham 

 Land, were rich in results and of greal scientific 

 value, made experimental exposures of Petri plates for 

 possible bacteria in the air. He found positive growths 

 hall ol hi> culture media, claiming that a 

 1 - be exposed foi tw houi s for one 

 mm to settle on it. His conclusion is, on the 

 evidence ol examinations of soil and on account of 

 the unprecedented weather conditions of his Antarctic 

 station, thai the organisms hi obtained from the air 

 were impurities carried into it by the wind from the 

 soil. 



Di. Gazert, 2 when frozen in the pack-ice to the 

 not th of Kaisei Wilhelm II. Land, sought for bac- 

 teria in the atmosphere by making cultures of freshly 

 fallen snow. The cultures were found in ever) 

 instance to be sterile. 



Dr. Pirie, 3 during his voyage in the VVeddell Sea, 

 exposed plates and tains i n Mi. crcw's-nesl lai the 

 I the mainmast) of the Scotia, at the longest for 

 twenty hours, with negative results. During the 

 winter months at Scotia Baj he was unsuccessful in 

 similar experiments, as also during the summer. He 

 ds, too. that plates of agar and media (for de- 

 nitrifying organisms) were expo d or top of the deck- 

 laboraton during the voyage in the VVeddell Sea in 

 [903. He considered the last-named cultures to be 

 isfactory, owing to the possibility of contamina- 

 tion from the ship and from spray. "Growths of 

 (apparently) Staphylococcus pyogenes albus and of a 

 yellow coccus, possibly Staphylococcus pyogenes 

 citreus, were obtained, and also denitrifying 



-•lis." 



Willi tli'is, evidenc before us it is instructive to 

 learn that Dr. Atkinson, of (apt. Scott's British 

 Antarctic Expedition (1910 i, ' h made bac- 



teriological examinations of snow. 4 "Atkinson is 

 ■ tain that hj ha- isolated a ven motile 

 bacterium in the snow. I: is probably air-borne, and, 



though no bacteria have 1 found in the air, this 



ma\ In- carried in upper currents and brought down 

 by the snow. If correct, it is an interesting dis- 

 covery." 



tly, so fai hack as iSn,. it is the record of 

 Nans, n in " Farthest North" thai In- made frequent 



miccoscopii examinations during thi second summer 

 of fresh-water pools on th of the North Polar 



Ugae ami diatoms wen proved to germinate 

 at tlie bottom of these pools, providing the food 

 material of infusoria and flagellata. Bacteria, he 

 were occasionally observed. Again, Nansen 



noticed that in places the -ml f the snow was 



Sprinkled with dust, and he was led, after more 



ided inquiries, to regard the phenomenon as 



universal over 'he North Polai sea. lie attributes 



this fact to floating dusl being carried by lofty air- 



1 " Balcteriotogische Studien wah-end der Schwedischen Sudpolar-Expe- 

 dition (1001-3).'' (Siorkholm, 1008.) 



Denlncbc Sudi t«i Experfitioi (Jntersuchungen uber 



Meerobalueiien unrl ihren Rinfluss iuf den Sloffwechsel in Meere 

 "Noteson Antarctic Bacteriologr." (Edinlmrch, iqi?.) 

 J "Scott'n Last Expedition,*" vol. i-. p. 211- (1011.) We have been 

 unable 10 far to confer with Dr. Atkinson with reference to his actual results 

 and genera! codcId 



hs from southern lands and then descending to 

 in face in falling snow . 



Doubtless, too, one maj infei thai equatorial air- 

 currents at a high altitude coi ads of dust- 

 motes towards the South Pol.. hen the) descend, 

 free or clinging to snow-particles, over the" great ice- 

 1 apped continent ol Antarctica. And as evidence 

 inwards the probable truth of this speculation we 

 have been able to furnish some isolated observations. 



The locus of the main base of the Australasian 

 Antarctic Expedition in Adelie Land , a i ularly 

 fitted for research of a general characlei on i, and 

 snow, since here the great inland plateau undulates 

 downwards in nt-i'e'-fields, declining gradual h for 

 hundreds of miles, to fall abruptly in glacial slopi - 

 to the sea In fact, we were on the verge of the 

 continent, with no naked mountains or outcropping 

 nunataks 5 encircling us to the south, so far as wi 

 were able to judge from sledging journeys into the 

 interior. That is to say, there were in the hinterland 

 no indigenous bacteria of Antarctic soil liable to con- 

 taminate the ice and snow, and as an additional safe- 

 guard, so to speak, there was a continuous torrent of 

 air always blowing towards the north. The average 

 hourly velocity of the wind during our two years' 

 sojourn in Adelie Land was actually almost fifty miles 

 per hour. The main base with its few rocks was at 

 s.a-level, and behind it mounted the glacier back to 

 the vast, upland plain which extends southwards, for 

 the most part at a height of 6000 ft., across the crown 

 of the Pole, itself at an altitude of more than 10,000 ft. 



[The results which were obtained from an examina- 

 tion of frozen algae and frozen seaweed led us to 

 inquire further into the bacterial content of the glacier- 

 ice — apparently as pure as distilled water ! And so 

 the organic content of frozen algae makes a suit- 

 able point of departure in considerations of a general 

 character, for in these dirty green lumps of ice are 

 represented practically the whole of the low life which 

 exists and actively multiplies in Antarctica : algae, 

 diatoms (unicellular algae), protozoa, rotifera, and 

 bacteria. The algae (including the diatoms) are uni- 

 versally found, according to the scientific reports of 

 other Antarctic expeditions, as marine or fresh-water 

 types in the ice-girt zone surrounding the continent. 

 In Adelie Land one became accustomed to note in the 

 summer-time that certain of the thawed pools among 

 the rocky ridges were filled with a greenish slime — 

 the filamentous, multicellular alga;.] 



On comparing results in Adelie Land and in Aus- 

 tralia, it is evident that at least four species of 

 bacteria exist in the frozen alga? : — 



(1) Gram-positive cocci, with fine, white colonies, 

 liquefying gelatine very slowly, were almost invariably 

 obtained in cultures. 



(2) A gram-positive, sporing bacillus spreading as an 

 abundant, pale, wrinkled, and adherent growth on all 

 media. 



(;,) Gram-positive, chained, sporing bacilli, occurring 

 a- a while, profuse growth on all media. In cover- 

 slip preparations of the ice chained bacilli were always 

 seen. 



(4) Short gram-positive bacilli, showing on agar a 

 milkv-white growth, which afterwards became yel- 

 lowish in tint. 



The fart of the mere presence of bacterial life in 

 fiozen algae would not seem remarkable along the 

 fringe of the continent, where lichens and mosses 

 thrive during the short periods of warmer weather, 

 and where there is a continuous accession of low 

 I i r. from the sea, the soil, and animals. It is only 



■ The Western Party, under Mr. V. H. Bicke-ton. discovered a small 

 piece of rock on the snow at a heifrht of 1000 ft. . t7 miles south-west of the 

 Hut in Adelie Land. This was afterwards identified in Melbourne by 

 Prof. Slceats and Mr. Stillwell : 



NO. 2550, VOL. 102] 



