Dumhle and Hariris — Galveston Deep Well. 41 



a greater thickening toward the Gulf. Even at the depth 

 attained the drill has not yet penetrated the sandstones, clays 

 and browncoals of the Fayette Beds as shown at the typical 

 localities in Fayette county, but is still in the sands and limy 

 clays which overlie them. 



Although the landward extension of these beds may come 

 today somewhere in the area of the Gulf slope our investiga- 

 tions have, up to this time, failed to bring to light any locali- 

 ties which furnish marine invertebrates of an age later than 

 the Claiborne. So far all the fossils found above that horizon 

 are in fresh water deposits of Miocene, Pliocene, and Pleisto- 

 cene age, and consist entirely of vertebrates. 



The Paleontology. — Gilbert D. Harris. 



The conclusions drawn from a study of the molluscan 

 remains* obtained from this well, may be summarized as fol- 

 lows : 



1. Of the 11 species obtained from samples numbered from 

 1 to 10 inclusive, all, except anew form of JEriphyla, are recent 

 and well known. In all probability therefore the strata passed 

 through between depths ranging from to 450 feet must be 

 referred to a post-Tertiary or Pleistocene epoch. The small 

 Eriphyla will probably be found recent on the Gulf shore. 



2. The fauna is so sparse between numbers 10 and 61 in- 

 clusive that it is unsafe to attempt to state just where in the 

 upper Tertiary it should be placed. In fact beds included 

 between depths 450 and 1500 may not be Tertiary at all but 

 Pleistocene. The undescribed, and probably for the most part 

 extinct species occurring from depths 1500 to 2150 feet show 

 conclusively that these beds are Tertiary. 



3. The fossils obtained from samples numberd 61 to 91 

 inclusive show that this part of the well section must be refer- 

 red to the Miocene series. Moreover, it is quite evident that 

 upon the whole the fauna represented is that of the upper 

 rather than the lower Miocene. Out of about 72 species, 26 

 are still living on the Atlantic or Gulf coast of the United 

 States, while 6 more survive only in the Pacific. Of the 36 

 new or doubtful forms probably the great majority are extinct, 

 though it is unsafe to predict what will yet be found in the 

 Gulf of Mexico. Area Carolinensis, Turritella subgrundifera 

 var. Chione, sp. nov. of west Florida Miocene, Terebra, n. sp. of 

 west Florida Miocene and J^fatica eminidoides of the West 

 Indian Miocene may be regarded as characteristic species, leav- 

 ing no doubt, when taken in connection with the foregoing 



*For a full account of the species obtained see Geol. Surv. Tex., 4th Annual 

 Report. 



