GEOLOGY AND PALEONTOLOGY OP THE CANAL ZONE. 71 



ones, the last formed chamber on the ventral side making up a large 

 part of the area of the test, sutures distinct, curved, slightly de- 

 pressed, more so on the ventral side ; wall smooth except for the usual 

 fine punctations; aperture ventral near the umbilicus. 



Length 0.60 mm., breadth 0.40 mm. Cat. No. 324674. 



The only record for this species from Panama is from the Gatun 

 formation, U.S.G.S. No. 6035, in gray green, fine grained, sandy 

 shell marl, near Mindi Hill. This species, described by d'Orbigny 

 from Cuba, seems to be a common species in the American Miocene. 



PULVINULINA CONCENTRICA Parker and Jones. 



Plate 25, fig. 1. 



Pulvinulina concentrica (Parker and Jones, MS.) H. B. Brady, Trans. Linn. 

 Soc. London, vol. 24, 1864, p. 470. pi. 48, fig. 14.— H. B. Beady, Rep. 

 Voy. Challenger, Zoology, vol. 9, 1884, p. 686, pi. 105, figs. lo-c. 



Description. — Test biconvex, oval; peripheral margin rounded; 

 chambers comparatively few, usually seven in the last formed coil, 

 sutures covered by clear shell material joining with the carinal border 

 and often covering a large portion of the test, both above and below, 

 especially toward the center; wall smooth, finely punctate; aperture 

 a narrow slit on the peripheral portion of the ventral side. 



Diameter 1.2 mm. Cat. No. 324675, U.S.N.M. 



The only specimen of this species is from the Gatun formation, 

 U.S.G.S. No. 6035, in gray green, fine grained, sandy shell marl near 

 Mindi Hill. The specimen as will be seen from the figure is very 

 typical. 



PULVINULINA MENARDII (d'Orbigny). 



Plate 25, figs. 2, 3. 



Rotalia menardii d'Orbigny, Ann. Sci. Nat., vol. 7, 1826, p. 273, No. 26; 



Modeles, No. 10. 

 Pulvinulina menardii Owen, Journ. Linn. Soc. London (Zool.), vol. 9, 1867, 



p. 148, pi. 5, fig. 6. — H. B. Brady, Rep. Voy. Challenger, Zoology, vol. 9, 



1884, p. 690, pi. 103, figs. 1, 2. 



Description.- — Test plano-convex, ventral side convex, dorsal side 

 nearly flat; compressed, umbilicate; peripheral margin thin, slightly 

 lobulated, carinate; chambers five or six in the last formed coil; 

 sutures distinct, limbate and broad on the dorsal side, curved, on the 

 ventral side more depressed, not limbate, nearly straight; wall 

 smooth, finely punctate; aperture extending peripherally from the 

 umbilicus, usually with an overhanging lip. 



Diameter up to 1 mm. Cat. Nos. 324676-8, U.S.N.M. 



Specimens apparently belonging to this species so widely dis- 

 tributed in the present oceans were obtained in the Gatun formation 

 at U.S.G.S. No. 6035 in gray green, fine grained, sandy shell marl, 



