O. Meyer—Species in the Southern Old-tertiary. 461 
27. [have Lucina Mississippiensis C. only from Jackson and 
this is the only exception to the rule, to compare only speci- 
mens. But this Lucina is very characteristic and agrees exactly 
a the figure and cuneate i ere ap ere species. 
A species of Lue in Jackson, and not very 
Ae ws Vicksburg, which j is a ubor icles and rather flat. Lateral 
culated is covered with ire tm striz, less n rous on 
— posterior side, which have a tendency to become prominent 
en 
n the carina and near the margins, ac ntire. This species 
is not named as it may perhaps be identical with Conrad’s Lucina 
Claibornensis, * although Conrad says in his description “ inequi- 
later al.” He describes this species from Claiborne, but from a 
‘group at the base of Claiborne Bluff, bral to an older divi- 
ae ot the Eocene than the Claiborne grou 
Cardium Nicolleti C., from J ackson, oa Cardium diversum 
©. cute Vicksburg have only quantitative differences in the orna- 
mentation. 
nus Cytherea seems here to vary very much, It i 
not only difficult to find out relations between the species, but 
even to separate the species, especially in Claiborne, when the 
material of the lowest and highest Claibornian aah part IT) is 
mixed. In Jackson the genus is rarest and my material from 
this locality poor. One perfect specimen pats beh Cytherea 
Jucksonensis, n. sp., agrees with Cytherea Hydi Lea, bu 
narrower hinge. The size of the hinge in Claiborne, ‘however, is 
35. A neg enone Tellina in Jackson is a larger and stoute 
ariety, var. robusta, of a Vicksburg species, which I deter led 
nn pote Bey ocunsnde s C. A young Jackson specimen has 
the same form as one of he stouter Vicksburg specimens. 
36. ackson occur fragments, which seem to differ merely 
in size ah Periploma a Olaibornensis Lea sp., which mace a a 
is known Ai in hen fragments. The Jackson form may 
called var. parv 
37. In J ioe occurs a species of Mactra, bec is almost 
equilateral, but otherwise does not differ from ’ Mact a pygmaca 
Lea, from Claiborne. As the forms vary in both h looalisves they 
are most probably to be related. The Jackson specimens are very 
Similar or identical with a species in Dc ic which is perhaps 
what Conrad called Mactra As athe 
38. A rnata, occurs in Jackson. It is 
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the shana is mostly water-worn. Ina specimen from Claiborne 
cannot find any difference. A specimen from Vicksburg is rela- 
tively higher, 
* Am. Jour. Conch., 1865, p. 146. 
