NEM. PAL.] 



MOLLUSCOIDA. 



313 



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

 111., vol. 8, pi. 77, Kaskaskia Gr. 



clausa, Ulrich, 1884, 

 (Fistulipora ? clausa,) 

 Jour. Cin. Soc. Nat. 

 Hist., vol. 7, p. 47, 

 Kaskaskia Gr. 

 eximia, Ulrich, (in 

 press,) Geo. Sur. 111., 

 vol. 8, pi. 77, Kaskas- 

 kia Gr. 

 Mitodema, Ulrich, 1882, 



rlG.494. MeeKOpO- Trmr C*,\n Srn ^Jnt 



ra clausa. Aper- i _ ,f.:' 



cular cover x 50. Hist., vol. 0, p. 150. 



Syn. for. Enallopora. 



dnctosa, see Enallopora cinctosa. 

 NEMATAXIS, Hall, 1887, Pal. N. Y., vol. 6, p. 

 74. [Ety. nema, thread ; axon, axis.] 

 Ramose, solid, bifurcating, cells arising 

 from a filiform axis, apertures oval, in 

 parallel rows, separated by ridges ; sur- 

 face marked with monticules, destitute 

 of cell apertures, and extending across 

 the branch, give it an annulated ap- 

 pearance. Type N. fibrosus. 



fibrosus, Hall, 1887, Pal. N. Y., vol. 6, p. 

 74, Up. Held. Gr. 



simplex, Hall, 1887, Pal. N. Y., vol. 6, p. 



193, Ham. Gr. 



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

 111., vol. 8, p. 401. [Ety. nema, thread ; 

 poros, pore.] Slender, ramose, contin- 

 uous above the pointed basal extremity ; 

 zocecia subtubular, short, arranged in 

 a radial manner around one or two 

 minute axial tubes ; apertures ovate or 

 subcircular, with peristome, generally 

 arranged between longitudinal ridges; 

 one or two diaphragms occasionally 

 present. ,Type N. quadrata. 



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

 111., vol. 8. pi. 29, Galena Gr. 



delicatula, Ulrich, (in press,) Geo. Sur- 

 111., vol. 8, pi. 29, Galena Gr. 



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

 111., vol. 8, pi. 29, Trenton Gr. 



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



vol. 8, pi. 29, Galena Gr. 

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

 111., vol. 8, p. 374. [Ety. proper name.] 

 Irregularly intertwining, flattened 

 branches, sometimes laminated ; zooecia 

 tubular, with diaphragms in the "ma- 

 ture " region ; apertures circular, with a 

 granose peristome; interspaces wide, 

 occupied by numerous angular meso- 

 pores, that more or less isolate the 

 zooecia ; walls of both the zocecia and 

 mesopores thin, and in the mature 

 region traversed longitudinally by tu- 

 buli ; the interzooecial spaces are filled 

 with a calcareous deposit, into which 

 the tubuli continue, but in which the 

 mesopore walls become unrecognizable ; 

 mesopores with thick and numerous 

 diaphragms. Type N. ponderosa. 



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

 vol. 8, pi. 33, Hud. Riv. Gr. 



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



111., vol. 8, pi. 34, Trenton Gr. 

 ODONTOTRYPA, Hall, 1887, Pal. N. Y., vol. 

 6, p. xvii. [Ety. odous, tooth; trupa, 

 opening.] Distinguished from Lichen- 

 alia, by the oblique trilobate, closely 

 arranged cell apertures, with strongly 

 elevated, denticulated margins, forming 

 a crescentic projection over the aper- 

 ture. Type O. alveata. 



alveata, Hall, 1881, (Lichenalia alveata,) 

 Trans. Alb. Inst., vol., 10, p. 10, and Pal. 

 N. Y., vol. 6, p. 85, Up. Held. Gr. 

 ORTHOPORA, Hall, 1887, Pal. N. Y., vol. 6, 

 p. xiv. [Ety. orthos, straight; poros, 

 pore.] Zoarium ramose, solid; cell 

 apertures arranged in parallel, longitu- 

 dinal rows ; intercellular space solid, or 

 occupied near the surface by minute 

 tubuli ; no septa. Type O. regularis. 



bispinulata, Hall, 1884, (Callopora bispin- 

 ulata,) Rep. St. Geol., p. 14, Hani. Gr. 



ornata, Hall, 1887, Pal. N. Y., vol. 6, p. 

 184, Ham. Gr. 



regularis, Hall, 1874, (Trematopora regu- 

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

 Hist., p. 105, Up. Held. Gr. 



reticulata, Hall, 1887, Pal. N. Y., vol. 6, 

 p. 179, Ham. Gr. 



rhombifera, Hall, 1874, (Trematopora 

 rhombifera,) 26th Rep. N. Y. St. Mus. 

 Nat. Hist., p. 106, Up. Held. Gr. 



scutulata, Hall, 1881, (Trematopora scutu- 

 lata,) Trans. Alb. Inst., vol. 10, p. 6, 

 and Pal. N. Y., vol. 6, p. 70, Up. Held. Gr. 

 PACHYDICTYA, Ulrich, 1882, Jour. Cin. Soc. 

 Nat. Hist., vol. 5, p. 152. [Ety. pachys, 

 thick ; dictyon, net.] Zoarium com- 

 posed of large, thick, branching fronds; 

 cells ovate, separated by interstitial 

 tubes ; diaphragms in both sets of 

 tubes; median epithecal plates perfo- 

 rated by minute foramina. Type P. 

 robusta. 



conciliatrix, Ulrich, 1886, 14th Rep. Geo. 

 Sur. Minn., p. 76, Trenton Gr. 



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

 vol. 8, pi. 33, Trenton Gr. 



fimbriata, Ulrich, 1886, 14th Rep. Geo. 

 Sur. Minn., p. 75, Trenton Gr. 



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

 vol. 8, pi. 31, Hud. Riv. Gr. 



foliata, Ulrich, 1886, 14th Rep. Geo. Sur. 

 Minn., p. 73, Trenton Gr. 



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

 vol. 8, pi. 31, Hud. Riv Gr. 



occidentals, Ulrich, 1886, 14th Rep. Geo. 

 Sur. Minn., p. 75, Trenton Gr. 



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

 Hist., vol. 5, p. 173, Trenton Gr. 



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

 111., vol. 8, pi. 31 and 32, Hud. Riv. Gr. 

 PALESCHARA, Hall, 1874, 26th Rep. N. Y. St. 

 Mus. Nat. Hist., p. 107. [Sig. ancient 

 Eschara.] Incrusting expansions ; cells 

 polygonal, oblong, separated by thin 

 solid walls ; maculee present ; no spini- 

 form tubuli or diaphragms. Type P. 

 incrustans. 



