TROPICAL OUTFIT 105 



In briefly stating above the chief theories of the 

 formation of atoll and barrier reefs, we have en- 

 deavoured to make clear the fact that all observations 

 made by the traveller will be of value. Let him, if 

 his time is limited, take up one point the structure 

 of the reef beneath his feet, the interrelations of the 

 organisms on its surface, the reactions of corals to 

 their environment, the feeding of corals, the relative 

 importance of corals and algae, the currents in the 

 passages, the formation of sand and mud, the action of 

 solution and erosion, the topography (especially 

 sections) of the outer and lagoon slopes, the plankton 

 within and without the barrier or atoll reef, etc. He 

 will do most service and interest himself more by 

 making himself a thorough master of one point, instead 

 of day after day superficially examining different parts 

 of the reef, and speculating without any precise or new 

 data on the method of its formation. In particular, for 

 fringing and barrier reefs observations are required as 

 to the causes of the formation of their channels. In 

 many places they are connected with the outflow of 

 streams off the land, but in as many others no such 

 connection is observed, and all notes on their formation 

 will be interesting. The residents' statements require 

 to be listened to with respect, but the greatest caution 

 must be observed in accepting them in lieu of scientific 

 evidence. 



C. Hints for Tropical Outfit. 



Dress. For ordinary tropical dress, suits of white 

 duck or twill are recommended, with the ordinary 

 canvas tennis-shirt and tie, white canvas shoes, and a 

 broad pith solar topee. The traveller should have thin 

 drawers or suspenders and a few broad body belts in 

 case of digestive troubles. 



