110 OIL FIELDS OF TEXAS-LOUISIANA COASTAL PLAIN, [bull. 212. 
No. 107. Collected 18 feet below surface and 171 feet below tide level, on beach, 
at "B." Same as No. 106. 
No. 108. Collected 30 feet below surface, at same place as No. 107. Same as No. 
107. 
No. 109. Collected from surface, uncovered at low tide, west of west jetty, Sabine 
Pass, about 600 feet from landward end, at "C." This sample con- 
sists of two kinds of mud, one black, the other greenish-yellow in 
color. In the dark-colored mud the shells were numerous. The 
greenish-yellow mud was plentifully supplied with diatom shells and 
contained living diatoms of the species Navicula and Pleurosigma. 
The entire sample of 115 grams yielded a trace of oil. The sample 
was from mud showing oily film on surface. 
No. 110. Collected 5 feet below surface, in same place as No. 109. Many shells; 
no living diatoms; no oil. 
No. 111. Collected 6.8 feet below surface, expjosed at extremely low tide, 200 feet 
west of west jetty, 3,500 feet from its landward end, at "D." Few 
shells; no diatoms; no oil. 
No. 112. Collected 6 feet below surface, which is covered at mean low tide, 300 
feet west of west jetty, 5,500 feet from its landward end, at "'E." 
Same as No. 111. 
No. 114. Collected 4 feet below surface, covered by 2 feat of water, at mean low 
tide, west of west jetty, 3,200 feet from its landward end, at i 'F.' , 
Shells no more numerous than in No. 111. 100 grams of mud yielded 
a trace of oil. 
No. 115. Collected 10 feet below the surface, which is covered by a few inches of 
water at low tide, 250 feet east of east jetty, 50 feet from edge of 
marsh, at " G." Few whole shells; no living diatoms; no oil. 
No. 1 1<>. ( lollected at surface, same place as No. 115. Few shells; living diatoms 
present; no oil. 
No. 117. Collected 2 feet below surface covered by 9^ feet of water, 6,000 feet 
west of west jetty, at " H." No living diatoms: some shells; no oil. 
"Diatom shells are found in all the samples, but they are not abun- 
dant in a single one. They are, however, more abundant in samples 
Nos. 109 and 116 than in any of the others. Both of these samples 
were collected from the surface of the mud, while all the others were 
collected from below it. In each of the samples collected from 2 to 8 
feet below the surface, i. e., Nos. Ill, 112, 114, 115, and 117, a few 
shells are found. The shells are least abundant in samples Nos. 100, 
107, and 108, which were collected from 18 to 30 feet below the surface 
along the shore. 
"Living diatoms were found in the two samples taken at the sur- 
face, Nos. 109 and 110, but they were absent from all the samples 
which had been collected below the surface of the mud. The com- 
pact nature of the mud, which prevents free circulation of water 
and consequent renewal of the oxygen, is inimical to the existence of 
the diatoms. 
"The samples of mud were free of oil, except samples Nos. 109 and 
114. The latter is the mud from which the oil globules rise when 
stirred, and the occurrence of the oil in No. 109 is doubtless to be 
attributed to the same cause as will account for that in No. 114. The 
