182 JONES AND KirkBpy—QOn Carboniferous Ostracoda from Ireland. 
11. Leperditia subrecta (Portlock). 
_ (Plate x1., figs. 13, 14.) 
1843. Cypris subrectus [ta],. . Porttocg, ‘ Rep. Geol. Londonderry,” p. 316, pl. 
xxlv., fig. 130. 
1860. Cythere subrecta, . . . GrirritH, Journ. Geol. Soc. Dublin, vol. ix., 
p. 48. 
1866. Leperditia Okeni, var.sub- Jones & Kirxpy, Ann. Mag. Nat. Hist., ser. 3, 
recta, vol. xvill., pp. 39, 42-47; L. subrecta, pp. 
48-51. 
1864. - subrecta, . . Jones & Kirxpy, Rep. Brit. Assoc. for 1863, 
Trans. sections, p. 80. 
1884. 4 8 . . Jones, Proc. Berwicksh. Nat. Club, vol. x., p. 321, 
ple, 197.8. 
1886. 5 Hf . . Jones & Krrxsy, Quart. Journ. Geol. Soc., vol. 
Xi, polo. 
1887. a a . . Jones & Krirxsy, Proc. Geol. Assoc., vol. ix., 
p. 004. 
Sub-oblong, with rounded, not quite equal extremities, ventral margin gently 
convex, and hinge-line straight, as much as three-fourths of the length of the 
valve. In some larger specimens, the hinge-line is nearly five-sixths of the 
length of the valve, and thus the dorsal angles extend further to meet the terminal 
curves without any antero- and postero-dorsal slopes. Ocular tubercle sometimes 
present. Between these extreme modified Leperditian outlines and the typical 
LL. Okeni there are ‘‘intermediate gradations among the countless individuals that 
swarmed in the muddy lagoons everywhere in the Carboniferous period,” op. cit., 
1884, p. 322. 
Characteristic specimens of this fine species occur in the Cultra Shale; the 
valves always detached and somewhat flattened. Sir Richard Griffith, in 1860, 
gave asa locality —“ Yellow Sandstone ; Largamore, Bangor, Co. Mayo.” General 
Portlock referred to the Carboniferous shales of Tyrone, Derry, and Fermanagh. 
It is indeed more persistent than any other Ostracod in the Carboniferous strata 
of Ireland. 
It is known also from the Lower Mountain-limestone of Northumberland, 
occurring in a dark shale at Tweedmouth, with L. Scotoburdigalensis. 
LL. subrecta is easily distinguished from that much more common and typical 
member of the genus, Leperditia Okeni, by its usually larger size, greater relative 
length of carapace, and the less obliquity of its valves. Both species are found in 
