T^N. THA.] 



MOLLUSCOIDA. 



327 



biserialis, Swallow, 1858, Trans. St. Louis 

 Acad. Sci., p. 179, Up. Coal Meas. 



rectistyla, Whitfield, 1882, Ann. N. Y. 

 Acad. Sci., vol. 2, p. 220, Kaskaskia Gr. 

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

 III., vol. 8. [Ety. tainia, ribbon ; dictuon, 

 net.] Zoaria growing from a basal ex- 

 pansion into dichotomously divided 

 narrow branches or broad fronds; cell 

 structure very much as in some species 

 of Ptilodictya (P. pavonia, D'Orb.); 

 apertures elliptical or subcircular, sur- 

 rounded by a sloping area ; interspaces 

 ridge-like; both "hemisepta" present. 

 Type T. ramulosa. 



cingulata, Ulrich, (in 

 ^, ^^ press,) Geo. Sur. 111., 



^^j voL 8 > P 1 - 67 > Keokuk 



IBV Gr - 



frondosa, Ulrich, (in 

 press,) Geo. Sur. 111., 

 vol. 8, pi. 70, Keokuk 

 Gr. 



interpolata, Ulrich, 1888, 

 Bull. Denison Univ., 

 vol. 4, p. 80, Cuyahoga 

 Shale. 



ramulosa, Ulrich, (in 

 press,) Geo. Sur. 111., 

 vol. 8, pi. 67, Keokuk 

 Gr. 



ramulosa var. burling- 

 tonensis, Ulrich, (in 

 press,) Geo. Sur. 111., 

 vol. 8, pi. 67, Burling- 

 ton Gr. 

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



vol. 8, pi. 67, St. Louis Gr. 

 T^ENIOPORA, Nicholson, 1874, Geo. Mag. 

 Lond. n. s., vol. 1, p. 120. [Ety. tainia, 

 ribbon ; poros, pore.] Flattened linear 

 expansion ; dichotomous ; celluliferous 

 on both sides. Distinguished from 

 Ptilodictya and Stictoppra by a central, 

 longitudinal keel, which divides the 

 frond into two lateral halves, and by 

 promineu t cell-mou th s. Ty pe T. exigua. 

 exigua, Nicholson, 1874, Geo. Mag. Lond. 



n. s., vol. 1, p. 122, Ham. Gr. 

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

 111., vol. 8, pi. 

 42, Ham. Gr. 

 penni f or m i s, 

 Nicholson, 

 1874, Geo. 

 Mag, Lond. n. 

 8., vol. 1, p. 

 123, Ham. Gr. 

 subcarinata, 

 Hall, 1881, 

 (Stictppora 

 subcarinata,) 

 Trans. A 1 b. 

 Inst., vol. 10, 

 r 1Q1 anrfFiG. 527. Tseniopora penni- 

 P- /%' a " a formis. a, Natural size ; 6, 

 JrEL JN. I., transverse section en- 

 voi. 6, p. 261, larged; c, fragment en- 

 Ham. Gr. lar S ed ' 

 Thallistigma, Hall, syn for Fistulipora. 



FIG. 520. -Tsenio- 

 dictya cingulata. 



5 Tangential sec- 

 tion x50, show- 

 ing a transverse 

 lining of the cen- 

 tral region of the 

 walls, a character 

 often present 

 among the Ptilo- 

 dictyonidse. 



confertipora, see Fistulipora cpnfertipora. 



decipiens, see Fistulipora decipiens. 



densa, see Fistulippra densa, 



digitata, see Fistulipora digitata. 



inclusa, see Favicella inclusa. 



intercellatum, see Fistulipora intercellata. 



lamellatum, see Fistulipora lamellata. 



longimacula, see Fistulipora longimacula. 



micropora, see Fistulippra micropora. 



multaculeata, see Fistulipora multaculeata. 



plana, see Fistulipora plana. 



scrobiculata, see Fistulipora scrobiculata. 



segregata, see Fistulipora segregate. 



serrulata, see Fistulipora serrulata. 



sparsipora, see Prismppora sparsipora. 



spheroidea, see Fistulipora spheroidea. 



gubtilis, see Fistulipora subtilis. 



triangularis see Fistulipora triangularis. 



umbilicata, see Fistulipora umbilicata. 



variopora, see Fistulipora variopora. 

 THAMNISCUS, King, 1849, Ann. and Mag. 

 Nat. Hist., 2d ser., vol. 3, p. 389. [Ety. 

 thamniskos, little shrub.] Stems fre- 

 quently bifurcating more or less on one 

 plane ; celluliferous on the side over- 

 looking the imaginary axis; cellules 

 imbricated and arranged in quincunx; 

 gemmuliferous vesicles overlying the 

 cell apertures. Type T. dubius. 



cisseis, Hall, 1883, Rep. St. Geol., pi. 22, 

 fig. 23-30, Low. Held. Gr. 



diffusus, Hall, 1852, (Retepora diffusa,) 

 Pal. N. Y., vol. 2, p. 160, Niag- 

 ara Gr. 



fruticella, Hall, 1883, Rep. St. Geol. pi. 22, 

 fig. 33, Low. Held. Gr. 



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

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



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

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



multiramus, Hall, 1881, Bryozoans of the 

 Up. Held. Gr., p. 19, and Rep. St. Geol. 

 1883, pi. 26, fig. 1-5, Up. Held. Gr, 



nanus, Hall, 1881, Bryozoans of the Up. 

 Held. Gr., p. 19, Up. Held. Gr. 



niagarensis, 

 Hall, 1876, 

 28th Rep. 

 N. Y. St. 

 Mus. Nat. 

 Hist., p. 

 126, Niag- 

 ara Gr. 



nysa, Hall, 

 1883, Rep. 

 St. Geol., 

 pi. 22, fig. 



47-48, FIG. 528. Thamniscus 



Lower niagarensis. 



Held. Gr. 



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

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



pauciramus, Hall, 1884, Rep. St. Geol., 

 p. 60, Ham. Gr. 



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

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



ramulosus var. sevillensis, Ulrich, (in 

 press,) Geo. Sur. 111., vol. 8, pi. 62, Low. 

 Coal Meas. 



