Dates of the several Numbers of this Volume. 
Number XVI, pp. 1-36 for September, 1905. 
Number XVII, pp. 37-104 for April, 1907. 
Number XVIII, pp. 105-190 for August, 1907. 
Number XIX, pp. 191-240 for April, 1908. 
Number XX, pp. 241-269 for March, 1909. 
