AMEEICAIS^ SPECIES OF OKTHOPHRAGMINA AND LEPIDOCYCLINA. 



57 



Test comparatively thin with small central umbo — Con. 

 Test large, diameter 50 to 100 millimeters — Contd. 

 Umbo prominent — Continued. 



Surface reticulate or smooth, pillars few 

 lateral chambers 7 to 10 in a vertical 



column L. gigas. 



Test small, diameter 8 to 20 millimeters: 



Pillars absent, lateral chambers few, 4 to 6. 



L. fragilis. 



Pillars present, lateral chambers numerous: 



Embryonic chambers subequal, equatorial 



chambers hexagonal L. chaperi. 



Embryonic chambers very unequal, equa- 

 torial chambers rhomboid L. vaughani. 



Test thickened at center, not distinctly umbonate but 

 gradually thinning toward the periphery: 

 Test very strongly sellaeform: 



Pillars numerous, test small, diameter usually 



4 to 8 millimeters L. floridana. 



Pillars few, test small, diameter usually 8 to 12 



millimeters L. perundosa. 



Pillars absent, test larger, diameter usually 25 



millimeters or more L. undosa. 



Test not greatly thickened, slightly sellaeform: 



Centrally papillate, pillars largely in the central 

 region : 

 Diameter 25 to 35 millimeters 



L. schlumbergeri. 



Diameter 12 to 15 millimeters 



L. pseudomarginata. 



Surface finely papillate throughout: 



Lateral chambers 10 to 12 L. supera. 



Lateral chambers 7 to 8. L. mortoni. 



Surface smooth or reticulate, lateral chambers 



15 to 20 L. ocalana. 



Test not sellaeform, lenticular: 



Diameter 20 to 30 millimeters, center pustulate, 

 pillars numerous, increasing gradually in diam- 

 eter to the surface L. subraulinii. 



Diameter 10 to 15 millimeters, center pustulate: 



Pillars numerous, increasing to full diameter 



in first third of length, then uniform to 



the surface, not thickened at periphery 



L. marginata. 



Periphery much thickened L. dupUcata. 



Diameter less than 10 millimeters: 



Diameter 8 to 9 millimeters, chamber walls 



very thick L. crassata. 



Chamber walls thin, pillars absent: 



Surface smooth or reticulate, lateral 



chambers 10 to 12 L. canellei. 



Surface centrally pustulate, lateral cham- 

 bers 6 to 10 L. sumatrensis. 



Chamber walls thin, pillars present: 



Center pustulate, reticulate between, 

 diameter 2 to 5 millimeters, embryonic 

 chambers reniform, lateral chambers 



10 L. morgani. 



Center pustulate, smooth between, diam- 

 eter 5 to 7 millimeters, embryonic 



chambers reniform L. macdonaldi. 



Center pustulate, embryonic chambers 



several, unequal L. panamensis. 



Center papillate, lateral chambers 6 to 7 

 L. antillea. 



Lepidocyclina mantelli (Morton) Gumbel. 



Plates XII-XIV. 



NummuUtes mantelli Morton, Am. Jour. Sci., vol. 23, p. 



291, pi. 5, fig. 9, 1833; Synopsis of organic remains 



of the. Cretaceous group, p. 45, pi. 5, fig. 9, 1834. 

 Orbitoides (Lepidocyclina) mantelli (Morton) Giimbel, 



K.-bayer Akad. Wiss. Abh., vol. 10, p. 718, 1868 



(1870). 

 Orbitoides mantelli D'Orbigny, in Lyell, Geol. Soc. London 



Quart. Join-., vol. 4, p. 11, 1847 (1848); Prodome de 



paleontologie, vol. 2, p. 406, No. 1296, 1850. 

 Carpenter, Geol. Soc. London Quart. Jour., vol. 6, 



p. 32, pi. 6, figs. 20, 21, 31, 1850. 

 Carpenter, Parker, and Jones, Introduction to the 



study of the Foraminifera, pp. 298, 300, pi. 20, figs. 



5, 6, 8, 11, 1862. 

 Btitschli, in Bronn, Klassen und Ordnungen des 



Thier-Reichs, p. 215, pi. 12, fig. 22, 1880; in Stein- 



mann, Elemente de Palaontologie, vol. 1, p. 36, 



fig. K, 1888. 

 De Gregorio, Annales geol. paleont., a'oI. 8. p. 261, 



pi. 46, figs. 16, 17, 1890. 

 Lepidocyclina mantelli Lemoine and R. Douville, Soc. 



geol. France Mem., Paleontologie, No. 32, p. 10, 



pi. 1, fig. 4; pi. 2, fig. 18; pi. 3, figs. 7, 12, 1904. 

 Orbitoides mantelli mut. umbrellopsis De Gregorio, Annales 



geol. pdleont., vol. 8, p. 262, pi. 46, figs. 21-26, 1890. 



Test thin, flattened, circular, often slightly 

 undulate; adults from 25 to 35 millimeters in 

 diameter, in exceptional specimens 41 milli- 

 meters; central region slightly protuberant on 

 both sides of the test, the umbo thus formed 

 being limited to the central portion and only 

 2 to 3 millimeters in diameter; surface smooth 

 in well-preserved specimens, or slightly pus- 

 tulate, owing to the irregular elevation of the 

 outer walls of adjacent lateral chambers; in 

 eroded specimens irregularly scrobicixlate; 

 young specimens with the central umbonal 

 protuberance more marked than in adults. 



The horizontal section (PL XIII) shows 

 the irregular hexagonal equatorial chambei*s, 

 the annuli very irregular in width; lateral 

 chambers also generally hexagonal or at least 

 polygonal, without pillars; embryonic chambers 

 of the megalospheric form, two subequal, the 

 dividing wall straight. 



Vertical sections (PL XII, figs. 4, 5) show 

 the band of- equatorial chambers increasiag 

 somewhat in height toward the periphery, 

 where they make up almost the entire thick- 

 ness of the test; the lateral chambers broad 

 and low, several times as broad as high, over- 

 lapping instead of in regular vertical columns, 

 and thus showing the absence of pillars ; embry- 

 onic chambers of the megalospheric form, 



