788 TRANSACTIONS OF SECTION K. 



Mercurialis perennis is absent. Woods of intermediate character are found on 

 alluvial deposits and on the edges of tertiary deposits. 



On the ' clay with flints ' the distribution is closely connected with the depth 

 of the deposit, and as a result definite zonation frequently occurs. Analyses to 

 determine (i) the percentage of lime, (ii) the acidity, and (iii) the water content 

 in soils of varying depths are being performed. 



Observations have also been made on the distribution of the commoner mosses. 



During the latter years of the coppice growth a deep shade is produced and 

 few herbaceous plants occur. Those found can be grouped as : (1) plants little 

 or not affected by the shade, which usually flower early in the spring ; (2) dwarf 

 plants which persist in the vegetative state and rarely flower. 



During this period there is an increase in the amount of humus, probably 

 a simultaneous increase in acidity. Analyses are now being made to determine 

 these points. 



Felling causes a great increase in the light intensity, and the temperature of 

 the surface soil is increased. These changes result in a great increase in the 

 number of herbaceous plants. These may be divided into : (1) plants which 

 have persisted during the shade period, and many of which now develop 

 luxuriantly ; (2) woodland plants unable to exist in the shade period. These 

 are largely biennial, but a few annuals and perennials are found. 



The maximum development of herbaceous plants is reached during the third 

 year. After this they gradually diminish, on account of the increase of shade. 

 The shade condition of the vegetation is reached by about the tonth year. 



4. Report on the Survey of Clare Island.— See Reports, p. 301. 



5. Report on the Experimental Study of Heredity. — See Reports, p. 300. 



6. Report on the Structure of Fossil Plants.— See Reports, p. 301. 



