Jan. 1896.] BOTANICAL SOCIETY OF EDINBURGH. 499 



5. The Activity of Growth as shown by the Daily Amount 

 of Carbonic Anhydride exhaled. — Taking the production of 

 carbonic anhydride as the measure of growth during 

 germination, the period of greatest activity, with varying 

 quantities of moisture, was generally found to occur about 

 the third or fourth day, the period being generally some- 

 what delayed with increase of moisture, especially in the 

 case of the Scotch and Smyrna barleys. After this point 

 of greatest activity isi- reached, there is a gradual fall in 

 vitality to the end of the 14 days or so according to the 

 experiment. 



The progress of vital activity is well shown in the series 

 of curves on diagrams Figs. 6, 7, and 8. 



Four experiments, two with Hungarian barley, and two 

 with Scotch Chevalier, were performed to ascertain if, at 

 the period of greatest vitality, as indicated by the curve 

 of daily excretion of carbonic anhydride, the moisture 

 present in the embryo was also at its greatest amount. 

 The result showed that if the germination were stopped 

 about the fourth or fifth day, the moisture present in 

 the embryo was then at its greatest quantity, ranging from 

 70"94 per cent, to 74'o7 per cent., and considerably higher 

 than that found in any experiment lasting 14 days or so. 

 The curves relating to these four curtailed experiments 

 will be found on diagrams Figs. 4 and 5, and the numerical 

 results in all the tables at the end. 



This, then, is all I have to bring before you to-night. I 

 have only just mentioned as it were the results obtained, 

 as it would not be of interest to wade through a lot of 

 tables. The results of the work, if meagre, will have 

 served their end if they suggest to others, who have more 

 time at their disposal than I have, some line of inquiry 

 that will lead to an increase of our knowledge on many of 

 the obscure points connected with germination. 



