form shape, broad midventral ridge and dorsoja- 

 cent furrow, and the deeply pitted surface charac- 

 teristic of the species. 



Length of a figured specimen (PI. 3, Fig. 3a) 

 0.65 mm, height 0.40 mm, convexity 0.38 mm. 



Occurrence. — Rare in beds cited as Eagle Ford 

 (upper member of Atkinson) in age by P. L. and 

 E. Applin (written communication) from Escam- 

 bia Oil Company's State Line Land and Lumber 

 No. 1 well, Escambia County, Alabama, core sam- 

 ple 4,679-4,684 feet. 



Genus Alatacythere Murray and Hussey, 1942 



Alatacy there tokiana (Israelsky)? 



Plate 3, Figure 4 



Cytheropteron tokiana Israelsky, 1929, Arkansas 



Geol. Survey Bull. 2, p. 9, pi. 1A, figs. 8, 9a, b. 

 ? Cythereis tokiana Loetterle, 1937, Nebraska 



Geol. Survey, Second Ser., Bull. 12, p. 55, pi. 9, 



figs. 4a, b. 

 not Cythereis (Pterigocythereis) tokiana Bold, 



1946, Contr. to Study of Ostracoda, DeBussy, 



Amsterdam, p. 100, pi. 6, fig. 9. 

 Pterygocythereis cf. P. tokiana Swain, 1952, U. S. 



Geol. Survey Prof. Paper, 234-B, p. 85, pi. 9, 



figs. 1-3. 

 Alatacythere tokiana (Israelsky). Howe and Lau- 



rencich, 1958, Introd. Study Cretaceous Ostra- 

 coda, p. 45, text fig. 



Shell elongate-subquadrate in side view, highest 

 about one-fourth from anterior end; dorsal mar- 

 gin somewhat sinuous, about three-fourths of shell 

 length and with broadly obtuse cardinal angles ; 

 ventral margin gently convex, sinuous due to pos- 

 teroventral alate expansion; anterior margin 

 broadly curved, extended and bearing three or 

 four short blunt spines below, subtruncate above ; 

 posterior margin narrowly rounded, subacuminate 

 and strongly extended medially and bears six or 

 more short spines. Valves more or less com- 

 pressed, with greatest convexity ventromedian ; 

 posterior fifth of valves more strongly compressed 

 than remainder of shell. Left valve slightly larger 

 than right, extending beyond right most strongly 

 in cardinal areas. 



Ventral surface of middle two-thirds of each 

 valve strongly expanded as a sharp-crested, back- 

 ward directed ala. Anterior end provided with a 

 narrow submarginal rim that dorsally begins an- 

 terior to rounded eye tubercle and continues ven- 

 trally and posteriorly to form narrow crest or ala ; 



posterior margin also bears a narrow rim; pos- 

 terior to mid-dorsum is a backwardly directed 

 short ridgelike extension that projects beyond 

 dorsal margin ; general surface smooth. Internal 

 characteristics not seen in single specimen at 

 hand. 



Length of figured shell 0.93 mm, height 0.52 

 mm, convexity including alae 0.5 mm. 



Remarks. — In shape, alation, and submarginal 

 rim structures the present specimen is close to 

 A. tokiana, but perhaps is less pointed posteriorly 

 than is typical for the species; furthermore, the 

 internal characters are not known. 



Occurrence. — Beds of Eagle Ford age (upper 

 member of Atkinson Formation) , Humble Oil and 

 Refining Company's No. 1 Bennett and Langdale 

 well, Echols County, Georgia, core 3,700-3,710 

 feet. A similar form was described from beds of 

 Trinity ( ?) and pre-Trinity age in the Hatteras 

 Light well, Dare County, North Carolina (Swain, 

 1952, p. 85). 



Family Trachyleberidae Sylvester-Bradley, 1948 



Genus Cythereis Jones, 1849 



Cythereis pittensis Swain and Brown, n. sp. 



Plate 3, Figures 7a, b 



Shell elongate subquadrate in side view, highest 

 about one-fifth from anterior end; dorsal margin 

 nearly straight, except for irregularity due to 

 dorsal ridge and cardinal angles, about three- 

 fourths of shell length, with widely obtuse cardi- 

 nal angles; ventral margin gently convex, some- 

 what sinuous due to projecting ventral ridges; 

 anterior margin broadly rounded, somewhat ex- 

 tended below and fringed with about a dozen small 

 short spines ; posterior margin narrow, extended, 

 and angulated dorsad of midheight, truncate to 

 slightly concave above, bearing about five short 

 spines below. Left valve slightly larger than right, 

 extending beyond it in cardinal parts of shell. 

 Valves compressed, greatest convexity is postero- 

 median in position. 



Terminal margins of both valves provided with 

 narrow marginal rims; the anterior with knife- 

 edge crest ; the posterior is less elevated and bears 

 several of the marginal spines ventrally. Dorsal 

 margin bears a narrow, irregular, sharp-crested 

 ridge which trends from large rounded lucid eye 

 tubercle to posterior cardinal angle ; five spurs ex- 

 tend ventrally from inner slope of ridge and in 

 part connect as low ridges with corresponding 



£9 



