20 



from its mouth there are reefs in the middle of the bayou that 

 are exposed at low tides. The oysters making up the greater 

 number of these reefs are of very good size and quality. Dur- 

 ing the past winter some especially fine oysters were taken from 

 the reefs in from twenty to twenty-five feet of water. 



The bottom in the deeper part of the channel, between the 

 areas occupied by the oyster reefs, is composed of rather firm, 

 sticky mud, and very soft places are of rare occurrence. Along 

 the sides of the bayou in the shallow water the bottom is gen- 

 erally very soft, except near the mouth of the bayou where 

 there is considerable sand mixed with the mud. The salinity 

 of the water averaged 1.0128, and was very little affected by 

 the freshets. The amount of oyster food in the water was al- 

 ways large. 



There are no bays or lakes of any importance on the south 

 side of Bayou Grand Caillou for some five miles from its mouth, 

 Hackherry Bay, opposite the middle portion of Sister Lake be- 

 ing the first body of water of any size. This bay is about three 

 miles long and one and one-half miles wide. It opens into 

 Bayou Grand Caillou by a wide pass, and is connected by a 

 narrow bayou with Dog Lake at the head of Grand Pass des 

 Isles. The depth of water over the greater part of this bay 

 varies from two and one-half to four feet, but is considerably 

 deeper near the pass to Bayou Grand Caillou. On the north 

 side of the bay there are some considerable areas of hard bot- 

 tom, mostly where there have been old reefs. Over the greater 

 part of the remainder of the bay, the bottom is composed of 

 soft mud, in most places too soft to support seed oysters. There 

 are several hard areas in, or near, the mouths of small bayous 

 going off from the southeast corner of the bay; but here also 

 the hard places are those that were formerly occupied by nat- 

 ural reefs. The salinity of the water was 1.0112 in the central 

 part of the bay, and the supply of food organisms was abundant. 



Above Hackberry Bay, along the southern side of Bayou 

 Grand Caillou, there are several small bays opening into this 

 bayou and having connections through small bayous with Dog 

 Lake, or some of the other bodies of water farther south in the 

 marsh. In some of these there are some productive natural 

 reefs, besides many extinct ones. The old reefs afford about 



