32 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. 89 



LEPIDOCYCLINA (NEPHROLEPIDINA) VAUGHANI Cushman 



Plate 16, figs. 1-5 



1918. Lepidocyclina vanghani Cushman, U.S. Nat. Mus. Bull. 103, p. 93, pi. 27, 

 fig. 4 (not figs. I, 2, 3, 5 which represent L. miraflorensis Vaughan) ; 

 pi. 38. 



1920. Lepidocyclina vaughani Cushman, U.S. Geol. Surv. Prof. Pap. 125, p. 64, 

 pi. 22, fig. 5. 



1923. LepidocycUnn vaughani Vaughan, Proc. Nat. Acad. Sci., vol. 9, pp. 254, 



25s, 256. 



1924. Lepidocyclina (Nephrolepidina) vaughani Vaughan, Bull. Geol. Soc. 



Amer., vol. 35, p.' 798, pi. 33, fig. 9. 



Test flattish, center umbonate, periphery thickened ; lo mm or more 

 in diameter. 



Cushman's illustrations give a correct idea of the size, of the outHne 

 of the test as seen in plan, and of the shape, size, and arrangement 

 of the equatorial chambers, but he did not illustrate the detail of the 

 surface ornamentation, the embryonic chambers, nor a vertical section. 

 In 1923 I stated that embryonic chambers were nephrolepidine, and 

 in 1924 I published an illustration of the embryonic chambers of a 

 specimen from Half Moon Bay, Antigua. In the present paper 

 supplemental illustrations are published, and notes on them are made 

 as follows: 



Plate 16, figure 5, shows the nephrolepidine embryonic chambers, 

 X 20, and the minute, almost hirsute, angular papillae of the surface 

 just outside the central area. Figure 4 of the same plate is the periph- 

 eral part of the same photograph from which figure 5 was made. It 

 illustrates the equatorial chambers near the periphery. They are mark- 

 edly rhomboid in form. The decrease in the length of the radial 

 diameter at the periphery should also be noted. Figure i of plate 16 

 is a vertical section, x 20, of another specimen from the same 

 locality. It shows lateral chambers with open cavities, arranged in 

 regular tiers, separated by rather thin, but distinct, pillars. The 

 number of layers of chambers is considerable, 10 to 13, over the 

 center, but it decreases toward the periphery, where over the ex- 

 panded edge there are none. At the periphery the equatorial chambers 

 enormously increase in height and become radially crowded. The 

 specimens illustrated by plate 16, figures i, 4. 5, are topotypes from 

 U.S.G.S. locality no. 6021 (the same locality as no. 6673 in Cushman's 

 papers cited above), limestone along the relocated line of the Panama 

 Railroad, opposite San Pablo, Panama Canal Zone. 



The specimens illustrated by plate 16, figures 2, 3, are from Half 

 Moon Bay, Antigua, collected by W. R. Forrest. These specimens are 



