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Bulletin American Museum of Natural History. [Vol. XXXV, 



fishes and other enemies of the young pearl oyster, and through it the tide 

 flows and ebbs, carrying minute forms of food for the growing young. The 

 tide through it can also be controlled so that a sufficient covering of water 

 for the young oysters can be maintained. The canal is provided with 

 thatched covering throughout its entire length as a protection against 

 undue heat when the tide is low. A general view of the station is shown 

 in Fig. 27. The dividing barrier of masonry is seen extending to the 

 opposite shore; nearer it is somewhat hidden by the thatch shelters of the 

 cross sections of the canal. The general plan of the canal is indicated by 

 the following diagram: 



A closer view of the closely set roofed sections is presented in Fig. 28 

 taken from the protecting barrier of masonry, the open bay lying at the 

 right. Beneath the sun shelters of each section the young shells are laid 

 at low water, to be covered and fed by the tides. The shallow wire trays 

 containing the shells are placed on lattice racks centrally located in each 

 section, where they are supported above the bottom and exposed to the 

 free flow of the water. As the shells grow larger their cultivation is con- 

 tinued on the rocky bottom of the canal. Some of the wire trays are 

 shown in Fig. 29. 



A view of one of the spat collectors is shown in Fig. 30. It is a 

 heavy-framed, wire-covered crate, containing five shallow, latticed trays, 

 closely set with short upright pieces of lath, to which the young free- 

 swimming oysters attach when shell growth begins. 



This collector has been brought to the beach from its original position 

 in some part of the bay and hauled up the cemented grade by a chain and 

 windlass. A nearer view of one of its trays is shown in Fig. 31, containing 

 young shells from two to three months old. 



Fig. 32 shows the trays of the crate removed, and employees ready to 

 transfer young oysters to the shallow wire trays for placing in the canal. 

 Each operator is provided with small wire trays. 



The young shells at this stage are an inch or two in diameter, as indicated 

 in Fig 29. They are more or less covered with marine growths of various 

 kinds, which are for the most part removed. 



