70 BULLETIN : MUSEUM OF COMPARATIVE ZOOLOGY. 
limestone. Rounded grains are evident in the samples, and ovules and 
oólite occur at some depths. As to color, 1,475 feet is a decided gray, 
presenting a readily recognized contrast to 1,450 feet; from 1,500 feet 
to 1,775 feet the material is pretty uniform in color, and would be de- 
scribed as being light brownish gray, but dark brown spots due to iron 
oxide occur at 1,600 feet; 1,800 feet is light brown with many white 
particles (fossils, etc.); from 1,825 feet to 1,975 feet the samples are 
light brownish gray with a yellowish cast, or are light yellowish brown 
and contain more or less of the white particles. In all the samples there 
is a trace, or a little more, of the fine angular quartz sand, together 
with an occasional larger rounded grain. Determinable fragments 
of organisms are few in all the samples and almost absent in some. 
Foraminifera are by far the most abundant recognizable fossils, and they 
form a considerable percentage of the samples from 1,625 feet, 1,650 
feet, and 1,775 fect.  Textularia is the most numerously represented 
genus, with Orbitoides next. Amphistegina, Oristellaria, Orbitolites, and 
other genera, are also easily to be found. Other classes of organisms are 
not common, even lamellibranchs not being numerous except at 1,600 
feet. Corals are not abundant in any of the set, and seem to be entirely 
lacking from many of them. 
2,000 feet. — At this depth the rock loses its yellowish cast and be- 
comes a light brownish gray, contrasting somewhat with 1,975 feet. 
The rock seems to have been a rather solid limestone with porous por- 
tions. It was very fossiliferous, foraminifera being especially abundant, 
though other classes are well represented. The obtusely and the sharply 
conical Textularias are the most numerous and Orbitoides seems to be 
absent. 
Although the genus Orbitoides does not seem to be represented in the 
samples from depths above 900 fect from the surface, except sparingly 
at 800—850 feet, there seems to be no particular change in the rock until 
after 700 feet has been reached, and there is a marked transition between 
the sample from that depth and the one next above (675 feet). Оп ac- 
count of these facts I am inclined to place the approximate upper limit 
of the Vicksburg beds of the Eocene in this well at 700 feet below the 
surface of the ground. The lower limit of the Vicksburg is not easily 
made out.  Orbitoides seems to be the predominating foraminifer down 
to 1,450 feet inclusive. Between this depth and the next (1,475 feet) 
there is a decided change in color, and while Orbitovdes docs not dis- 
appear entirely at once, the two conical forms referred to Teatularia are 
much more numerous, Below 1,875 feet Orbitoides seems to be lacking. 
