NOTES ON RECENT RESEARCH. 



1129 



p. 589). Abstract of paper read before Section K of the British Associa- 

 tion, Belfast, 1902.— " Our first experiments were made with organisms 

 possessing varying degrees of resistance, the extremes in this respect 

 being represented by the sensitive Spirillum of cholera asiatica and the 

 resistent spores of Bacillus anthracis. Ten organisms altogether were 

 used and cooled down to —190° C, in the first instance for twenty hours 

 and eventually for seven days. These exposures did not produce any 

 appreciable impairment in the vitality of the organisms, either as regards 

 their growth or their characteristic physiological properties, such as pig- 

 ment and gas production, pathogenicity, &c. Amongst the organisms 

 tested were photogenic Bacteria, and these likewise preserved their 

 normal luminous properties ; and we were able, through the kindness of 

 Professor Dewar, to apply a still severer test, namely an exposure to the 

 temperature of liquid hydrogen (about —252° C), a temperature which is 

 as far removed from that of liquid air as is that of liquid air from the 

 average summer temperature. Ten hours' exposure to this temperature 

 had no appreciable effect upon the vitality of the micro-organisms tested." 

 The influence of prolonged exposure to the temperature of liquid air was 

 then tried. " The organisms employed were the Bacillus typhosus, B. 

 coli communis, Staphylococcus pyogenes aureus, and a Saccharomyces. . . . 

 Samples were taken and tested at intervals for a total period of six months. 

 In no instance could any impairment of the vitality of the organisms be 

 detected. The ordinary manifestations of life cease at zero, but at — 190° C. 

 we have every reason to suppose that intracellular metabolism must also 

 cease, as a result of the withdrawal of two of its cardinal physical con- 

 ditions, heat and moisture. It is difficult to form a conception of living 

 matter under this new condition, which is neither life nor death, or to 

 select a term which will accurately describe it. It is a new and hitherto 

 unobtained state of living matter — a veritable condition of suspended 

 animation." — R. I. L. 



Thuja. 



Thuja, A Morphological Study of. By W. J. G. Land (Bot. Gaz. 

 xxxiv. p. 249, No. 4, pis. i.-viii). — The development of the pollen-grain and 

 tube, of the archegonium and the ventral nucleus, is described. This is 

 followed by fertilisation, and the formation of the pro- embryo. — G. H. 



On the Ascent of Sap. 



Transpiration Stream, The Rise of the.— By E. B. Copeland 

 (Bot. Gaz. xxxiv. p. 161, No. 3 ; and p. 260, No. 4).— This is an his- 

 torical and critical discussion, and in part experimental. The author 

 considers the various views held, from Dutrochet's in 1837 to the present 

 day, adding at the close a very long bibliography. He is more especially 

 concerned with Dixon and Joly's theory of cohesion, which he finds 

 insufficient, observing : " Ten years ago Bohm alone imagined that 

 capillarity could play the leading role in the ascent of sap. It had been 

 tried and found wanting. Then it was named cohesion, and sprang at 

 once into popular favour." The chief hindrance to the theory is the 

 presence of bubbles when the tension is low and the transpiration active. 



