NORTH AMERICAN EAELY TERTIARY BRY020A. 



759 



13 O 



Affinities. This species differs from TubuHpora midwayanica in its less pro- 

 jecting, irregular, and incomplete fascicles. In its general aspect it much resembles 

 Tubvlipora lucida MacGillivray, 1884, from the Australian coasts. It differs from 

 it in its less salient tubes and its more oblique peristomes. These are insignificant 

 differences which a knowledge of the micrometric measurements of the Australian 

 species might overcome. 



Occurrence. Middle Jacksonian: Kich Hill, 5^ miles southeast of Knoxville, 

 Crawford County, Georgia (very rare). 



Holotype.Cnt. No. G5335, U.S.N.M. 



PLATONEA, new genus. 



Greek : -platos, in allusion to the ovicell occupying the entire zooecial width. 

 The ovicell is subsymmetrical, lobate, median, elongate, spread out between the 

 fascicles over the entire zoarial width. The gemmation is linear. " Oeciostome a 



short tube, developed on the 

 proximal side of one of the 

 series of zooecia, near its me- 

 dian end. Oeciopore directed 

 frontally, elongated trans- 

 versely and more or less 

 oval." (Harmer, 1915.) 



Genotype. - - Eeptotubi- 

 gera philippsae Harmer, 

 1915. 



Range. - - Vicksburgian- 

 Eeccnt. 



Historical. The form of 

 the zoarium is that of an 

 incrusting Idnwnea. Noting 

 the great difference between 

 this ovicell and that of Tu- 

 Intlipoi'n, Harmer in 1915, 

 believed that the old genus fieptotubigera of D'Orbigny might be restored but 

 unfortunately all the species of Reptotubigera have not the same ovicell and 

 to our great regret we, can recognize the genus of the French paleontologist only 

 for those species deprived of ovicell, in conformity with his definition and figures. 

 Affinities. This genus differs from Idmonea, which has the same fascicular 

 arrangement, in its lobate ovicell spreading between all the fascicles and not limited 

 to a single median part of the zoarium. It differs from TnbnHpora in its sub- 

 symmetrical ovicell, in its tubes little projecting above the ovicell, and in its linear 

 gemmation. 



Tubulipora serpens is provided with a zoarium like an incrusting Idmonea. 

 It is not a Platonea because its ovicell is irregularly lobate, not subsymmetrical 

 and because its small oeciostome is adjacent to any tube whatsoever. We repeatedly 

 have to remark that the zoarial form is of no value for generic classification. 



Willis. 



B "20 



FIG. 248. I'liitoiifii, new 

 A, B. Ovicelled lobe of. Platonea (Reptotubigera} itliil- 

 ac Harmer, 1915 o, oeciopore. 



