300 



MOLLVSCOIDA. 



[CVS. ENA. 



CYSTOPORA, Hall, 1881, Bryozoans of Up. 

 Held. Gr., p. 19. [Ety. kustis, bladder; 

 poros, pore.] Simple or branching sub- 

 cylindrical stipes ; cells arising from the 

 axis ; circular and subcylindrical below, 

 enlarged above the middle and becom- 

 ing ampullate, turning abruptly out- 

 ward below the apertures, which are 

 extremely contracted; cell-tubes ex- 

 posed more than half their length. 

 Type C. geniculata. 



geniculata. Hall, 1881, Bryozoans of the 

 Up. Held. Gr., p. 20, and Pal. N. Y., vol. 

 6, p. 103, Up. Held. Gr. 

 DIAMESOPORA, Hall, 1852, Pal. N. Y., vol. 2, 

 p. 158, and vol. 6, p. 19. [Ety. diame- 

 808, the part between ; poros, opening.] 

 Ramose, hollow, epitheca on inner sur- 

 face ; intercellular space solid ; surface 

 like Trematopora. Type D. dichotoina. 



camerata, Hall, 1883, (Trematopora came- 

 rata,) Rep. St. Geol. and Pal. N. Y., 

 vol. 6, p. 72, Up. Held. Gr. 



communis, Ulrich, (in press,) Geo. Sur. 

 111., vol. 8, pi. 39 and 41, Utica Slate. 



constricta, Half, 1874. (Trematopora con- 

 stricta,) 26th Rep. N. Y. St. Mus. Nat. 

 Hist., p. 104, Low. Held. Gr. 



dichotoma, Hall, 1852, Pal. N. Y., vol. 2, 

 p. 158, Low. Held. Gr. 



dispersa, Hall, 1879, (Trematopora dis- 

 persa,) 32d Rep. N. Y. St. Mus. Nat. 

 Hist., p. 150, Low. Held. Gr. 



vaupeli, Ulrich, (in press,) Geo. Sur. 111., 



vol. 8, pi. 39 and 41, Utica Slate. 

 DICHOTBYPA, Ulrich, (in press,) Geo. Sur. 

 111., vol. 8, p. 386. [Ety. dicha, double ; 

 trupa, opening.] Consisting of large 

 bifoliate expansions; the surface with 

 solid maculae ; zooecial and minute struc- 

 ture as in Cystodictya. Type D. foliata. 



elegans, Ulrich, (in press,) Geo. Sur. 111., 

 vol. 8, pi. 76, St. Louis Gr. 



expatiata, Ulrich, (in press,) Geo. Sur. 

 111., vol. 8, St. Louis Gr. 



flabellum, Rominger, 1866, (Fistulipora 

 nabellum,) Proc. Acad. Nat. Sci., Phil., 

 p. 9, St. Louis Gr. 



foliata, Ulrich, (in press,) Geo. Sur. 111., 

 vol. 8, pi. 42, Ham. Gr. 



grandis, Ulrich, (in press,) Geo. Sur. 111., 

 vol. 8, pi. 42, Niagara Gr. 



intermedia, Ulrich, (in press,) Geo. Sur. 

 111., vol. 8, pi. 76, St. Louis Gr. 



lyroides, Ulrich, (in press,) Geo. Sur. 111., 



vol. 8, pi. 77, St. Louis Gr. 

 DICRANOPOUA, Ulrich, 1882, Jour. Gin. Soc. 

 Nat. Hist., vol. 5, p. 166. [Ety, di- 

 kranos, two-pointed ; poros, pore.J Zo- 

 arium like Stictopora, but distinguished 

 by being composed of ligulate joints, 

 the edges being subparallel to near the 

 upper end, when they diverge and bear 

 two segments ; cell-mouths between 

 raised longitudinal lines ; no interstitial 

 cells. Type D. internodia. 



emacerata, Nicholson, 1875, (Ptilodictya 

 emacerata,) Pal. Ohio, vol. 2, p. 261, 

 Hud. Riv. Gr. 



fragilis, Billings, 1866,(Ptilodictyafragilis,) 

 Catal. Sil. Foss. Antic., p. 9, Hud. 

 Riv. Gr. 



t 



FIG. 471. Dicranopora internodia. Natural size 

 and magnified. 



internodia, Miller & Dyer, 1878, (Ptilo- 

 dictya internodia,) Cont. to Pal., No. 2, 

 p. 7, Hud. Riv. Gr. 



lata, Ulrich, 1882, Jour. Cin. Soc. Nat. 

 Hist., vol. 5, p. 166, Hud. Riv. Gr. 



nitidula, Billings, 1866, (Ptilodictya niti- 

 dula,) Catal. Sil. Foss. Antic., p. 9, 

 Hud. Riv. Gr. 



trentonensis, Ulrich, 1882, Jour. Cin. Soc. 



Nat. Hist., vol. 5, p. 167, Trenton Gr. 

 DIPLOCLEMA, Ulrich, (in press,) Geo. Sur. 

 111., vol. 8, p. 368. [Ety. diploox, double ; 

 klema, twig.] Ramose, ovate in cross 

 section ; zocecia tubular, long, appar- 

 ently moniliform proximally ; separated 

 internally by an axial lamina, from 

 which they gradually diverge to open 

 on the two sides of the compressed 

 branches; apertures prominent, isolated, 

 somewhat constricted and circular; ex- 

 ternal wall thin. Type D. trentonense. 



trentonense, Ulrich, (in press,) Geo. Sur. 



111., vol. 8, pi. 53, Trenton Gr. 

 DIPLOPORA, Young & Young, 1875, Proc. 

 Nat. Hist. Soc. Glasgow. [Ety. diploot, 

 double; poros, pore.] Very slender 

 straight stems, throwing off a few lat- 

 eral branches of equal dimensions ; ob- 

 verse or poriferous side, with two 

 ranges of zooecia apertures, and moder- 

 ately developed medium keel ; reverse 

 striated. Type D. marginalis. 



bifurcata, Ulrich, (in press,) Geo. Sur. 

 111., vol. 8, pi. 62, Kaskaskia Gr. 



biserialis, Ulrich, (in press,) Geo. Sur. 



111., vol. 8, pi. 62, Low. Coal Meas. 

 DISCOTRYPA, Ulrich, 1882, Jour. Cin. Soc. 

 Nat. Hist., vol. 5, p. 155. [Ety. diskos, 

 quoit; trupa, opening.] Free, thin, cir- 

 cular expansions; cells rhombpidal or 

 hexagonal; low monticules, with clus- 

 ters of large cells present ; no intersti- 

 tial cells or spiniform tubuli. Type D. 

 elegans. 



? devonira, Ulrich, 1886, Cont. to Am. Pal., 

 p. 25, Up. Held. Gr. 



elegans, Ulrich, 1879, (Chetetes elegans,) 

 Jour. Cin. Soc. Nat. Hist, vol. 2, p. 130, 

 Hud. Riv. Gr. 



ENALLOPORA, D'Orbigny, 1850, Prodr. d. Pa- 

 leont., t. 1, p. 22. [Ety. enalloz, changed ; 

 poros, pore.] Small bifurcating branches, 

 without connecting bars; cell-mouths 



