Tlie Sfrt(fi(jriipfni (}f X. W . Loit Islnrm. — Vaviilinii. 221 
llw Jdchson iiniJ Y ickslmnj sfdgeK. 
As pointed out by Dr. Lereh in his report on "Geology of 
the Hills of Louisiana,'' the Jackson and Yicksburg pass con- 
formably into eaeh other and resemble each other sf> closely 
lithologicallj^ tiiat the}' can be distinguished only by paleon- 
tologic characters. Both stages are largely characterized 
by calcareous clays. At the base of the Vicksburg are lig- 
nitic strata, as can be seen in the section about three miles 
south of Koselield in Datahoula i)arish. Dr. Ililgard^has no- 
ted a similar occurrence of lignitic clays and lignite at the 
V>ase of the >'icksburg at Vicksburg and north of Brandon in 
Mississi])pi. On account of the lithological similarities of 
these two stages the area occupied by them must for the pres- 
ent be treated as a unit. On the north the area is limited by 
the Claiborne series of beds, the known Jackson outcrops 
being at Montgomery on the Red river, at Tullos and two 
miles north of Rosefield in Catahoula parish, at Bunker Hill 
in Caldwell parish, and at Grand View on the Ouachita river. 
Mr. Harris, in his "Report on the Tertiary (ieology of Ar- 
kansas,"' on p. 182 states: "The exact point at which the 
Jackson stage reaches the Ouachita river is still unknown. In 
1884 Dr. Harlan described the genus liasilosa uni.s [Zeinjhxhui) 
l)efore the American Philosophical Society, giving as its lo- 
cality a point on the Ouachita river, fifty miles by land below 
Monroe. This means doubtless a locality not far from Grand 
\'iew." 
Hopkinsf makes no reference to Harlan's work, and from 
his statement, even giving a section, I am certain that he had 
been to Grand View. By the crooked road south from Mon- 
roe, Grand View is very near the locality referred to by Har- 
lan. I have Jackson fossils, submitted to me by the Louisi- 
ana Geological Surve}^ that came from two miles north of 
Rosefield, a point about five miles southwest of (irand \'iew, 
Hopkins mentions Zeuglodon bones having been found"where 
t he Harrisoiil)urg and Columbia road crosses the ('atahoula 
and Caldwell parish line.";]; This place corresponds very 
*A<rriciiltuff and (Jcol. (jf Miss., p. lO.S. ]S()(i. 
fFirsI I{<'1>. ba. (ii'ol. Siir\ . fi)!- isc.'.t. |iiih. ls;(i. 
+ ()p. cil.. p. !fi. 
