BUREAU OF SCIENCE PUBLICATION No. 18 

 VOLUME 1, FASCICLE 3 



EXPLANATORY NOTE 



It was originally intended to issue this work in three volumes, 

 the general introduction to be issued as a part of Volume 1 

 and the indices to form a part of Volume 3. Owing to the 

 extent of the introduction, the bibliography, and the indices, it 

 has been found best to issue all these data as Volume 4. 



IMPORTANT 



In binding Volumes 2 and 3 discard the title-page issued with 

 fascicle 5 of each of these yoluines and substitute therefor the 

 revised title-pages found at the end of Volume 4. 



Elmer D. Merrill. 

 MANILA, P. I., November 1, 1923. 



