that conclusions drawn are of a tentative nature, subject to modification as 

 the work ot analysis proceeds, and as further field work provides new ma- 

 terial for study. The principal objective of this report is to make available 

 the factual information and to provide a general basis upon which plans 

 for future field work may be laid. 



Figure 1. The 40-foot cruiser Explorer, especially designed tor the 

 expedition and bui!t by Wheeler Shipyard Co. 



Pvrsintnvi and Kquiptnvni 



The work of the expedition was under the leadership of Mr. Luis R. 

 Rivas, who also was responsible for the ichthyological studies and for the 

 direction of field investigations off Chile and Peru. Dr. F. G. Walton Smith 

 directed observations off Ecuador. Mr. and Mrs. Lou Marron, with Mr. 

 and Mrs. John Manning, were responsible for the capture of the greater 

 number of the billfish specimens examined. Travelling arrangements, the 

 location of field bases and general field management, were in charge of Mr. 

 Marron, assisted by Mr. Manning, who remained in the field during the 

 entire period of expedition. All members of the expedition gave assistance 

 in the collection of samples and in the measuring and examination of spec- 

 imens. Capt. Howard Thuet, and Mrs. Thuet, field secretary, were respon- 

 sible for keeping numerical data and logs. 



• 7 



