$10 



MOLLUSCOIDA. 



[HOM. LEI. 



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



111., vol. 8, pi. 32, Hud. Kiv. Gr. 

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



Minn., p. 82, Trenton 'Or. 

 minnesotensis, Ulrich, 1886, 14th Rep. 



Geo. Sur. Minn., p. 79, Trenton Gr. 

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



Hist., vol. 5, p. 243, Hud. Riv. Gr. 

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



Sur. Minn., p. 81, Trenton Gr. 

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

 Sur. Minn., p. 83. [Ety. homolrypa, a 

 genus; ellus, diminutive.] Zoarium 

 ramose; monticules wanting; intersti- 

 tial cells present ; zocecia small, moder- 

 ately thick walls, and cystoid dia- 

 phragms straight; spinifprm tubuli 

 numerous. Type H. instabilis. 

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



vol. 8, pi. 32, Hud. Riv. Gr. 

 granulifera, Ulrich, 1879, (Chetetes granu- 

 liferus,) Jour. Cin. Soc. Nat, Hist., vol. 

 2, p. 128, Trenton Gr. 

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



Sur. Minn., p. 83, Trenton Gr. 

 Hornera, Lamouroux, 1821, Expos. Method, 

 des genres de L'Ordre des Pol. [Ety. 

 proper name.] Not American Palaeo- 

 zoic. 



dichotoma, see Subretepora dichotoma. 

 ICHTHYOBACHIS, McCoy, 1844, Garb. Foss. 

 Ireland, p. 205. [Ety. ichthys, fish ; 

 rachis, backbone.] Bryozoum plumose, 

 consisting of a rachis, with short lateral 

 branches or pinnules; celluliferous on 

 one side ; cell apertures in two ranges 

 on the branches, and in three or more 

 on the main stem. Type I. newen- 

 hami. 

 nereis, Hall, 1874, 26th Rep. N. Y. St.Mus. 



Nat, Hist., p. 98, Low. Held. Gr. 

 IniOTRYPA, Ulrich, 1883, Jour. Cin. Soc. 

 Nat. Hist., vol. 6, p. 272. [Ety. idios, 

 peculiar; trupa, opening.] Parasitic, 

 interstitial cells angular, both cells with 

 diaphragms; spiniform tubuli present. 

 Type I. parasitica. 

 paraeitica, Ulrich, 1883, Jour. Cin. Soc. 



Nat. Hist., vol. 6, p. 273, Niagara Gr. 

 INTBAPORA, Hall, 1881, Bryozoans of the Up. 

 Held. Gr., p. 16. [Ety. intra, within ; 

 poros, pore.] Resembling Stictopora, 

 branches broad; intercellular spaces 

 regularly punctured or pitted, as if by 

 minute cell apertures; cells with 

 rounded mouths and short prostrate 

 portion ; intercellular 'space vesiculose. 

 Type I. puteolata. 



puteolata, Hall, 1881, Bryozoans of the 

 Up. Held. Gr., p. 16, and Pal. N. Y., 

 vol. 6, p. 97, Up. Held. Gr. 

 Intricaria, Defrance, 1823, Dictionnaire des 

 Sciences Naturelles. Not a Palaeozoic 

 genus. 



claihrata, see Subretepora clathrata. 



reticulata, see Subretepora reticulata. 



ISOTRYPA, Hall, 1885, Rep. St. Geol., p. 37. 



[Ety. isos, equal ; trupa, perforation.] 



Fenestelloid, having the branches con- 



nected by dissepiments, and with two 

 ranges of cell apertures, separated by 

 carinae, elevated and much thickened 

 above, connected by distinct lateral 

 processes; the reverse face has on or 

 near the dissepiments conspicuous 

 pores larger than the cell apertures. 

 Type I. conjunctiva. 



FIG. 490. Isotrypa conjunctiva. Celluliferous 

 side and noncelluliferous side, with pores on 

 the dissepiments. 



bifaria, syn. for I. conjunctiva. 



conjunctiva, Hall, 1881, (Fenestella con- 

 junctiva,) Trans. Alb. Inst, vol. 10, p. 

 143, and Pal. N. Y., vol. 6, p. 143, Up. 

 Held. Gr. 



consimilis, Hall, 1885, Rep. St. Geol., pi. 



2, fig. 14, Up. Held. Gr. 

 LABKCHIA, Edwards & Haime, 1851, Pol 

 Foss. des Terr. Pal., p. 297. [Ety. 

 proper name.] Bryozoum laminar, in- 

 crusting, or attached by part of the 

 base, and having the remainder cov- 

 ered by an epitheca ; surface covered 

 with rounded or elongated, solid, tu- 

 bercles, separated by an imperforate cal- 

 careous membrane ; internally it con- 

 sists of vertical columns extending from 

 the epitheca below, and terminating 

 above in the surface tubercles, the in- 

 terspaces between the columns consist- 

 ing of lenticular vesicles, the uppermost 

 layer of which gives rise to the seem- 

 ingly imperforate membrane between 

 the tubercles. Type L. conferta. Prob- 

 ably this genus belongs to the Protozoa, 

 and is related to the sponges. 



montifera, Ulrich, 1886, Cont. to Am. Pal., 



p. 33, Hud. Riv. Gr. 



LEIOCLKMA, Ulrich, 1882, Jour. Cin. Soc. 

 Nat. Hist, vol. 5, p. 141. [Ety. leios, 

 smooth ; klema, twig.] Ramose, lamel- 

 late, or parasitic; surface even; cell- 

 mouths small, rounded, surrounded by 

 interstitial cells ; tubes thin-walled ; 

 diaphragms remote ; acanthopores 

 abundant. Type L. punctatum. 

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



111., vol. 8, pi. 75. Kaskaskia Gr. 

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

 vol, 8, p. 301, Warsaw Gr. 



