64 



SHORTER CIONTRIBUTIONS TO GENERAL GEOLOGY, 1919. 



and biuader tiiuii liigli; those toward the pe- 

 riphery are thick-walled, slightly higher than 

 wide, and the vertical walls slightly convex 

 and thickened; lateral chanabers very low and 

 broad, in central region with not more than six 

 chambers in a vertical cohimn, generally lessen- 

 ing in number toward the periphery, where 

 there may be but one or even none. No 

 pillai-s apparent. 



Type specimens from U. S. G. S station 

 7194, Ocala limestone, at mouth of cavern 

 about 200 yards southwest of wagon bridge 

 over Chipola River, east of Marianna, Fla.; 

 bed 4 of section; C. W. Cooke and W. C. Mans- 

 field, collectors. Specimens also occur at the 

 following stations : 



3760. Tivola tongue of Ocala limestone on Georgia 

 Southern & Florida Railroad half a mile south of Tivola, 

 Ga.; S. W. McCallie, collector. 



6747. Ocala limestone at Steamboat Point ou west side 

 of Sepulga River at sharp bend near middle of sec. 20, T. 

 3 N., R. 13 E.. Escambia County, Ala.; ('. W. Cooke, 

 collector. 



7337. Left bank of Suwannee River above bridge of 

 Florida Railway, Suwannee County, Fla., northeast of 

 Mayo; C. W. Cooke, collector. 



7348. Left bank of Suwannee River about 1 mile above 

 Troy Springs, Fla.; C. W. Cooke, collector. 



Tliis is a very thm species and consequently 

 fragile. The outer equatorial chambers, w^iich 

 are unprotected by the lateral chambers, have 

 thickened walls that give greater strength to 

 this thin peripheral portion. 



The species seems to be characteristic of 

 Ocala limestone. 



Lepidocyclina chaperi Lemoine and R. Douvilte. 



Plate XXn, figures 3, 4. 



Lepidocyclina chaperi Lemoine and R. Douville, Soc. geol. 

 France, Paleontologie, Mem. 32, p. 14, pi. 2, fig. 5, 1904. 

 Cushman, U. S. Nat. Mus. Bull. 103, p. 92, pi. 35, 

 figs. 1-3; pi. 36, 1918. 



Test of medium size, diameter from 8 to 20 

 millimeters, circular in outline, somewhat 

 saddle-shaped; central portion slightly thick- 

 ened, thence gradually and evenly thmning 

 toward the periphery; surface where well pre- 

 served slightly papillate, usually roughened by 

 erosion, toward the periphery often somewhat 

 reticulately depressed above the equatorial 

 chambers. 



Vertical section usually curved; lateral cham- 

 bers numerous, breadth much greater than 

 height, columns separated by distinct pillars, 



com])aratively few except in the central region, 

 where there are a few larger than the others; 

 embryonic chambers of the double type, the 

 two chambers nearly equal in size and sepa- 

 rated by a straight common wall. 



The horizontal section shows similar condi- 

 tions of the embryonic chambers and distinctly 

 hexagonal equatorial chambers. 



Lemoine and R. Douville described this spe- 

 cies from Panama (Haut-Chagres, San Juan). 

 Tlie specimens figured came from U. S. G. S. 

 station 6025, from marl at the south end of 

 Bohio Ridge switch, on the relocated line of 

 the Panama Railroad, collected by T. W. 

 Vaughan and D. F. MacDonald, and from sta- 

 tion 0019-f, on the west side of the Gaillard Cut 

 near Las Cascadas. These specimens seem to 

 represent the microspheric form of this species. 



A specimen from station 6526, Chiriqui, 

 Canal Zone, shows a section which from its 

 general proportions seems to suggest strongly 

 L. cJuiperi. 



H. Douville^ records this species from Salt 

 Mountain, Ala., but the material from the high- 

 er levels at this locality seems to be referable to 

 L. sujyera (Conrad). 



Lepidocyclina vaughani Cushman. 



Plate XXII, figure .5. 



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

 103, p. 93, pi. 37, figs. 1-5; pi. 36, 1918. 



Test of medimn size, 10 millimeters or more 

 in diameter, flat; surface somewhat umbonate 

 in the central portion, gradually sloping to 

 the peripheral portion, the outer half of wliich 

 is nearly flat. Wall smooth except for fine 

 papillae. The peripheral portion of tlie test 

 when well preserved is typically much thick- 

 ened, the edge thick and squarely truncated. 



Tlie horizontal section shows the peculiar- 

 ity of the chambers, many of which, especially 

 those of the outer peripheral portion, are 

 rhomboid; those of tlie inner portion are more 

 tyjiical and hexagonal. These are showTi 

 especially well on the sections of the larger 

 specimens, those of the smaller specimens 

 showing only the regular hexagonal character 

 of the earlier chambers. 



No very good vertical sections were obtained 

 in the thin sections, but several accidental 

 sections show the characters well. The embry- 



1 Compt. Rend., 1918, pp. 264, 265. 



