DATES OP ISSUE OP THE PARTS OF VOL. XX. 



Part 77, pp. 1-64, plates 1-10, November 19, 1908. 

 Part 78, pp. 65-154, plates 11-21, May 18, 1909. 

 Part 79, pp. 155-314, plates 22-36, September 29, 1909. 

 Part 80, pp. 315-336, plates 37-43, February, 1910. 

 Title-page, Contents and Introduction, February, 1910. 



(iv) 



