PAC. — PHI.] 



CCELENTERATA. 



199 



solitarium, Hall & Whitfield, 1873, 23d 

 Rep. N. Y. St. Mus. Nat. Hist., p. 232, 

 Chemung Gr. 



Fig. 201.— Pachyphyllum woodmani. 



woodmani, White, 1870, (Smithia wood- 

 mani,) Geo. Sur. Iowa, vol. 1, p. 188, 

 Chemung Gr. 

 Pachypora, Lindstrom, 1873, Ofversight af 

 K. Vetensk Akad. Forhandl., p. 14. 

 [Ety. pachys, thick ; poros, pore.] Den- 

 droid or frondescent; corallites 

 polygonal or subcylindrical, walls 

 thickened toward their mouths, by con- 

 centric layers of sclerenchyma ; calices 

 annular, oblique, or semilunar ; septa 

 obsolete or mere spiniform projections ; 

 tabulae complete, remote ; mural pores 

 few, irregular, and often large. Type 

 P. lamellicorni8. 

 fischeri, Billings, 1860,( Alveolites fischeri,) 

 Can. Jour. n. s., vol. 5, p. 256, Up. 

 Held. Gr. 



frondosa, Nicholson, 

 18 7 4, (Alveolites 

 frondosus,) Geo. 

 Mag., vol. 1, p. 15, 

 and Rep. Pal. On- 

 tario, p. 57, Ham. Gr. 

 o r n a t a, Rominger, 

 1876, (Dendropora 

 ornata,) Pal. Foss. 

 Corals, p. 62, Ham. 

 Gr. 

 PaljEOCYclus, Edwards 

 & Haime, 1849, 

 Comptus rendus, t. 

 29, p. 71. [Ety. 

 palaios, ancient; 

 kuklos, circle.] Coral - 

 lum circular ; fos- 

 sula deep, broad, 

 circular; septa thick, not numerous or 

 cemented together. Type P. porpita. 

 kirbyi, Meek, 1868, Trans. Chi. Sci., p. 



85, Devonian. / 



rotuloides, Hall, 1852, 

 (Cyclolites rotu- 

 loides,) Pal. N. Y., 

 vol. 2, p. 42, Clin- 

 ton Gr. 

 Pal^ophyllum, B i 1- 

 lings, 1858, Rep. of 



Prog. Geo. Sur. Can., p. 168. [Ety. 

 palaios, ancient; phyllon, leaf.] Fascicu- 



FlG. 



202.— Pachypora 

 frondosa. 



Fig. 203.— PalBeocyclus 

 rotuloides. 



late or aggregate ; corallites surrounded 

 by a thick wall ; septa extending the 

 whole length ; tabulae absent or rudimen- 

 tary ; increase by lateral budding. Dis- 

 tinguished from Streptelasma by form- 

 ing aggregate masses. Type P. rugo- 

 sum. 



Fig. 204.— Palceophyllum divaricaus. 



divaricans, Nicholson, 1875, Pal. Ohio, 

 vol. 2, p. 220, Hud. Riv. Gr. 



rugosum, Billings, 1858, Rep. of Progr. 

 Can. Geo. Sur., p. 168, Trenton Gr. 

 Palseotrochis, Emmons, 1856, Geo. Rep. 

 Midland counties of North Carolina. 

 Two species were mentioned, P. major 

 and P. minor, both of which are sup- 

 posed to be concretions, and therefore 

 inorganic. 

 Peronopora, Nicholson, syn. for Monti- 



culipora. 

 Petraia, Munster, 1839, Beitrage zur Petre- 

 faktenkunde, vol. 1, p. 42. [Ety. 

 petraios, that grows among rocks.] 

 Simple, turbinate ; septa of one or two 

 sizes, the larger extending from the 

 walls to the center, where they are 

 more or less twisted ; no tabulae or con- 

 necting vesicular plates. Type P. 

 decussata. Streptelasma is by some re- 

 garded as a synonym, by others as a 

 subgenus, and by others as quite dis- 

 tinct. The forms in this country which 

 have been referred to Petraia are all, 

 probably, Streptelasma, and for that 

 reason I have so referred them. 



angulata, see Streptelasma angulatum. 



aperta, see Streptelasma apertum. 



fanningana, see Streptelasma fannin- 

 ganum. 



forresteri, Honeyman, 1868, Acadian 

 Geology, p. 594. A catalogue name. 



latuscula, see Streptelasma latuscula. 



logani, see Streptelasma logani. 



minganensis, see Archaeocyathus min- 

 ganensis. 



ottawensis, see Streptelasma ottawense. 



pulchella, see Streptelasma pulchellum. 



pygmsea, see Streptelasma pygmaeum. 



rustica, see Streptelasma rusticum. 



selecta, see Streptelasma selectum. 



waynensis, see Streptelasma wayneuse. 

 Phillipsastrea, D'Orbigny, 1849, Note Sur. 

 des Polypiers Fossiles, p. 12. [Ety. 

 proper name ; aster, star.] Composite, 

 resembling Strombodes, but differing in 

 the septa of neighboring corallites 



