300 BULLETIN 106, UNITED STATES NATIONAL MUSEUM. 



DISTANSESCHARELLA JACKSONICA, new species. 



Plate 42, fig. 1. 



Only the figured specimen has been found, and it is unfortunately very incom- 

 plete. The function of the thick smaller zooecia is unknown. Smitt has cited 

 something analogous to them in Membramporella agasstsi Smitt. 1873, 1 where they 

 are rare. 



The zoarium incrusts an Idmonca. 



Occurrence. Middle Jacksonian: One-half mile southeast of Georgia Kaolin 

 Company Mine, Twiggs County, Georgia (very rare). 



Holotype.C&t. No. 04029, U.S.X.M. 



FIG. 85. Genus Gcphyrotcs Norman. 1903. 



A-E. Gephyrotcs nitido-punctata Smitt, 1808. A. Zooecia, X 19. (After Smitt, 1868.) 

 B. Zooecia, showing avieularia (at'), ovicell loci, ami spiramen (./>). C. Var. spitzbcrgensis 

 Norman, 1903. Anterior portion of an ovicelled zooecium. (After Norman, 1003.) I). The 

 anterior portion of a zooecium, to show the structure of the bridge and oral opening, a, costula 

 bifurcated; b, solid outspread costula; c, spiramen; d, lateral foramen; I. lumen; Ip, lumen pore. 

 E. Costular system, X 83. (After Nordgaartl. 1903.) rf, loop of the costula; la, lacuna; Ip, 

 lumen pore. 



Genus GEPHYROTES Norman, 1903. 



1903. Gephyrotcs NORMAN, Notes on Natural History of East Finmark, Annals and Magazine 

 Natural History, ser. 7 ,vol. 12, p. 100. 



The costules are narrow. They are at first largely separated for half of their 

 length; they are afterwards curved and join the adjacent costules, thus forming 

 n complete arch; this ai-ch is followed by large lateral lacunae. The two distal 

 costules bifurcate to form a spiramen in the zooecial axis. A pair of avieularia 

 with mandible pointing upwards is developed on the side walls of the aperture. 

 The ovicell is subglobose and imperforated. No dietellae. 



' Genotype. Gephyrotes (Cribilina} nitido-punctata Smitt, 1863. 



Range. Jacksoniau-Recent. 



We have classified in this genus all the Costulidae provided with a spiramen. 

 But, under these conditions, all the costules are not identical. In their general 



1 1875, Smitt, Floridan Bryozoa, Svenska Vetenskaps-Akademiens Handling:)!-, vol. 19, p. 11, pt. 5, fig. 10(i. 



