62 



SHORTER CONTRIBUTIONS TO GENERAL GEOLOGY, 1919. 



7 miles above Bainbridgc, Ga/; bluff on cast 

 side of Flint River back of old factory about 

 2 miles above Bainbridgc, Ga.^, Hales Landing, 

 on Flint River 7 miles below Bainbridgc, Ga.^ 

 I have seen and checked material from all 

 these localities. 



The species is a very large one in at least 

 some of its individuals, but the range hi size is 

 very considerable, and it may be very likel}' 

 that the largest specimens are the microspheric 

 form of the species and the smaller ones the 

 megalosphe:^ic. The material is not sufficiently 

 well preserved to permit a study of the embry- 

 onic chambers in detail. 



There is evidently a progressive develop- 

 ment in form of the test and character of the 

 ornamentation of the surface. In the smaller, 

 younger specimens the umbonal portion is 

 strongly raised and the whole test is promi- 

 nently papillate, although the umbonal portion 

 shows the paj^illae most prominently. In older 

 specimens the papillae are largely limited to 

 the central region and the umbonal region of 

 the test is not nearly so much raised in compari- 

 son as in the young. This character is similar 

 to that seen in the young of L. mantelli and 

 already noted. 



At the followmg Georgia stations T. W. 

 Vaughan collected molds of the exterior, 

 probably of L. georgiana: 3618, west end of 

 wagon bridge, Albany; 3624, 1 mile east of 

 Americus; 3625, 2 miles east of Americus. A 

 single specimen showing equatorial chambers 

 of a Lepidocyclina, which may be L. georgiana, 

 was obtained at Saffold, Early County, Ga. 

 The rock is very hard and filled with pits, 

 indicating possibly in part a small nummulitc. 

 Tills material is similar to that obtained at 

 station 7094, on the west bank of Flint River 

 at the Atlantic Coast Line Railroad bridge at 

 Bainbridgc, which also has the same character. 



A specimen from station 4959, Rich Hill, 

 Crawford County, Ga., collected by L. W. 

 Stephenson, may be the young of this species. 



L. georgiana is characteristic of the Ocala 

 limestone occurring at many stations with 

 several species of OrthopTiragmina. 



Tlie following additional stations in Georgia 

 have furnished material which, though not 

 inwardly well preserved, probably should be 

 referred to L. georgiana: 



1 Vaughan, T. W., in Veatch, Otto, and Stephenson, L. W., Georgia 

 Geol. Survey Bull. 26, pp. 320, 329, 1911. 



2 Idem, p. 332. 



3293. Left bank of Flint Pdver at Bainliridge, Decatur 

 County; A. IT. Brooks, coUoctor. 



3380. Base of bluff at Little Ilorsoshoe Bend, just below 

 tlie mouth of Blue or Russell Spring, Flint Pviver, Decatur 

 County; T. W. Vaughan, collector. 



3768. Twelve miles north of Bainbridge and 3 miles west 

 of Flint River; S. W. McCallie, collector. 



(illO. Steamboat landing, Bainbridge. 



6159. Red Bluff, Flint River; L. W. Stephenson, 

 collector. 



6160. Flint River, north of Blue Spring, 4 miles below 

 Bainbridge, Decatur County; L. W. Stephenson, collector. 



6161. Flint River at Bainbridge; L. W. Stephenson, 

 collector. 



7082. Hales Landing, west bank of Flint River, 7 miles 

 southwest of Bainbridge ; T. W. Vaughan, C. W. Cooke, 

 and W. C. Mansfield, collectors. 



7098. Red Bluff, Flint River, 7 miles above Bainbridge; 

 C. W. Cooke, collector. 



7106. Flint River at mouth of Spring Creek, Sumter 

 County, 2 miles above Seaboard Air Line Railway bridge ; 

 C. W. Cooke and J. E. Brantly, collectors. 



7127. East bank of Flint River in Mitchell County, a 

 quarter of a mile below Normans Ferry, in loo.=e blocks ex- 

 cavated from channel; C. W. Cooke and .1. E. Brantly, 

 collectors. 



7129. East bank of Flint River 1 mile below Wiadell's 

 Landing, about 6 miles above Red Bluff; C. W. Cooke, 

 collector. 



The species is also present in Alabama at 

 station 6747, in the Ocala limestone at Steam- 

 boat Point, on the west side of vSepulga River 

 at sharp bend near middle of sec. 20, T. 3 

 N., R. 13 E., Escambia County; C. W. Cooke, 

 collector. 



In its gross appearance L. georgiana is sug- 

 gestive of L. gigas Cushman, from Antigua, but 

 the papillate character is much more clearly 

 shown in L. georgiana and is correlated in the 

 vertical section with the numerous pillars. 



The largest specimens of L. georgiana seem 

 to show definite senescent characters in the loss 

 of the papillate character of the surface, which 

 becomes much smoother in the adult, and in 

 the relatively less prominent umbo in the larger 

 specimens. The senescent feature is especiall}* 

 shown in the pillars, which in the younger speci- 

 mens are conical, the outer end being the ^\'idest, 

 whereas in the largest specimens they become 

 smaller in the outer portion and as a result in 

 section are somewhat fusiform. 



Some of the external molds of the specimens, 

 especially those obtained 3 miles southwest of 

 Boykin station. Miller County, Ga., by C. W. 

 Cooke, show even more clearly than the speci- 

 mens themselves the relative abundance and 

 distribution of the external papillae formed by 

 the distal ends of the pillars. 



