OYSTER BOTTOMS IN MATAGORDA BAY. 49 



which is conditioned by the accident that the schooner Kate Ward 

 was wrecked there several years ago and her hull furnished the one 

 requisite previously lacking, a solid support for the attachment of 

 the multitude of swimming oyster fry which annually throng the 

 surrounding water. So with every oyster bed in the bay to-day, 

 the substratum on which it lies differs probably not at all from the 

 surrounding bottom, as was proved in the case of many of them by 

 the investigation carried on by the survey. It is apparent, therefore, 

 that the absence of oysters on a given area is not an evidence, of its 

 inherent lack of adaptation to oyster culture. A further investi- 

 gation is necessary to determine the facts. 



In this survey the quality of the bottom was determined by means 

 of the sounding pole at upward of 100,000 places in all parts of the 

 bay, and in many localities this was supplemented by probings to 

 determine the character of the substratum. These examinations 

 disclosed a marked uniformity of the distribution of the bottom 

 materials. 



Along the northwestern shore there is, except in the vicinit}^ of the 

 mouth of the Colorado, a narrow fringe of hard mud, the original 

 bottom left by the erosion of the prairie loam as the shores gradually 

 receded under the action of the waves. A large part of this bottom 

 is bare for long periods during the winter. Off the mouth of Live 

 Oak Bay the belt of hard mud is much wider than elsewhere, reaching 

 from the north shore well on to the large oyster bed in the middle of 

 the bay off Dressing Point. On the southeastern side there is a cor- 

 responding but generally wider strip of sand washed from the shores 

 and drifted by the winds which sweep across the peninsula from the 

 sand hills on the Gulf. In many places the sand is compact and 

 apparently stable, but often it tends to shift and undoubtedly close to 

 the shore line it is all liable to be seriously disturbed under the 

 influence of the heavy gales which sometimes visit the Gulf coast. 

 Forked Bayou Reef lies just beyond the edge of this sand in com- 

 paratively deep water, yet it is stated, and the physical evidence 

 gathered by the survey tends to substantiate the claim, that during 

 the extraordinary gale of 1875 this bed was partially overwhelmed by 

 sand swept upon it by the waves. This was an unusually violent gale, 

 however, and in general it may be stated that the outer edge of the 

 sand zone, where it lies as a thin stratum on the subjacent mud, is 

 comparatively stable. This is particularly the case where the sand 

 belt is broad, as on the Idlebach Flats or generally below Tiger Island, 

 where its edge meets the mud at a depth of 5 or 6 feet. Between the 

 two strips above described, one on each shore, the entire bottom of the 

 bay, save on the natural beds, is composed of a deposit of moderately 

 soft mud of considerable depth, though in places in the 4 upper bay 



