AMERICAN SPECIES OF OKTHOPHRAGMINA AND LFPIDOCYCLINA. 



77 



In Cuba it occurs usually in company with 

 L. morgani, and in this connection it is inter- 

 esting to note that both species are listed by 

 Lemoine and R. Douville from all four of the 

 stations in Spain and from three of the four 

 stations in France. 



This species may easily be distinguished 

 from L. morgani by its lack of pillars. The pus- 

 tulate appearance of L. sumatrensis is due to 

 the convex surface of the lateral chambers, 

 those of adjacent columns being of unequal 

 height at the surface. A figure, evidently of 

 this species, by Miss O'Connell ^ shows a verti- 

 cal section at the left. The specimen came 

 from a limestone quarry at Arroyo Seboruco, 

 12 miles from Felton, Cuba. 



Lepidocyclina macdonaldi Cushman. 



Plate XXXIV, figures 1-3. 



Lepidocyclina macdonaldi Cushman, U. S. Nat. Mus. Bull. 

 103, p. 94, pi. 40, figs. 1-6, 1918. 



Test circular, rather small, about 5 to 7 

 millimeters in diameter, thickest in the central 

 region, thence gradually sloping to the periph- 

 ery, which for a short distance in from the 

 edge is nearly fiat; wall rather smooth except 

 the central portion of the umbonal region, 

 which has a few pustule-like raised spots at the 

 surface ends of the vertical pillars. 



The vertical section shows the test widest in 

 the middle, gently sloping nearly to the periph- 

 ery, edges nearly parallel for a short distance 

 to the peripheral edge or even slightly increas- 

 ing in thickness. Lateral chambers in the cen- 

 tral portion in definite vertical columns, occa- 

 sionally slightly overlapping. Equatorial cham- 

 bers not increasing very rapidly in height in 

 megalospheric specimens, those at the periph- 

 ery hardly more than double the height of 

 those near the center of the test. Embryonic 

 chambers in the megalospheric form large, 

 usually of two nearly equal chambers, but in 

 oblique cutting these may appear somewhat 

 unequal. (See PI. XXXIV, fig. 2.) 



Horizontal sections show chambers somewhat 

 similar to those of L. vaugJiani but with the 

 inner half of two walls at nearly right angles, 

 the outer wall broadly rounded. The obhque 

 section (PI. XXXIV, fig. 3) shows the pillars. 



The type locality for this species is U. S. 

 G. S. station 6523, orbitoidal limestone 



1 Kemp, J. F., Am. Inst. Min. Eng. Trans., vol. 51, fig. 6, 1916. 



2 miles north of David, Panama, collected by 

 D. F. MacDonald, Specimens were abundant 

 at this station, occurring with L. panamensis 

 and L. multiplicata. 



Lepidocyclina panamensis Cushman. 



Plate XXXIV, figures 4-Q. 



Lepidocyclina panamensis Cushman, U. S. Nat. Mus. Bull. 

 103, p. 94, pi. 39, figs. 1-6; pi. 42, 1918. 



Test circular, small; central portion very 

 strongly umbonate, thick, rapidly decreasing 

 in thickness peripherally; peripheral portion 

 thin and flattened; the raised central portion 

 only one-third to one-fifth the entire diameter, 

 which ranges from 3 to 6 millimeters, with 

 occasional specimens, perhaps representing the 

 microspheric form, 10 or 12 millimeters in 

 diameter; surface smooth except for the um- 

 bonal portion, which has a few large pustule- 

 like projections marking the ends of the internal 

 pillars. 



The vertical section shows very peculiar em- 

 bryonic chambers, not the usual type for Ameri- 

 can species, but with a broad and much 

 flattened central chamber two to four times as 

 broad as high and a compressed, partly encir- 

 cling chamber, in section usually cut on the 

 opposite sides of the central chamber. These 

 central chambers in section are nearly as wide 

 as the whole mnbonal portion of the test. In 

 some specimens there seems to be an irregular 

 mass of three or four more or less nearly spheri- 

 cal chambers. Lateral chambers usually about 

 twice as wide as high, the outer wall often 

 somewhat arched toward the exterior of the 

 test, arranged in vertical columns. Pillars not 

 distinct except in the central portion, where 

 there are a few strong ones increasing rather 

 rapidly in diameter toward the periphery, usu- 

 ally about 9 or 10 chambers in a vertical col- 

 umn in the center of the umbilical region. The 

 peripheral region has but a thin coating of 

 lateral chambers, the last-formed layer present 

 only on the outer half of the periphery and 

 often none at aU present on the last quarter of 

 the test toward the periphery, the surface being 

 made up by the upper and lower walls of the 

 equatorial chambers. Equatorial chambers 

 numerous, comparatively broad, the peripheral 

 waU convex outward toward the periphery, the 

 chambers at least as wide as high. 



In horizontal section the equatorial chambers 

 appear usually somewhat irregularly hexagonal 



