CONTENTS. 



REPORTS on an Exploration off the West Coasts of Mexico, Central and South America, 

 and off the Galapagos Islands, in charge of Alexander Agassiz, by the U. S. Fish 

 Commission Steamer "Albatross," during 1891, Lieut. Commander Z. L. Tanner, 

 U. S. N., Commanding. XXXVIII. Reports on the Scientific Results of the Expedi- 

 tion to the Tropical Pacific, in charge of Alexander Agassiz, by the U. S. Fish Com- 

 mission Steamer "Albatross," from August, 1899, to March, 1900, Commander Jeffer- 

 son F. MosER, U. S. N., Commanding. XX. Reports on the Scientific Results of 

 the Expedition to the Eastern Tropical Pacific, in charge of Alex.\nder Agassiz, by 

 the U. S. Fish Commission Steamer " Albatross," from October, 1904, to March, 1903, 

 Lieut.-Commander L. M. Garrett, U. S. N., Commanding. XXXI. The Annelida 

 Polych.\eta. By Ralph V. Chamberlin. 514 pp. 80 plates. July, 1919. 



