292 



MOLLUSCOIDA. 



[ANI. ARC. 



cingulata, Ulrich, 1882. Jour. Gin. Soc. 

 Nat. Hist., vol. 5, p. 254, Hud. 

 Riv. Gr. 



FIG. 449. Amplexopora cingulatn. Tangential 

 Kectlon x50, showing wall structure, and verti- 

 cal section x50. 



discoidea, Nicholson, 1875, (Chetetes 

 discoideus,) Ohio Pal., vol. 2, p. 206, 



Hud. Riv. Gr. 

 pustulosa, Ulrich, (in 

 press,) Geo. Sur. 111., vol. 

 8, pi. 36, Hud. Riv. Gr. 

 robusta, Ulrich, 1883, Jour. 

 Cin. Soc. Nat. Hist., vol. 

 6, p. 82, Hud. Riv. Gr. 

 septosa, Ulrich, 1879, (Atac- 

 topora septosa,) Jour. 

 Cin. Soc. Nat. Hist., vol. 

 2, p. 125, Hud. Riv. Gr. 

 superba, Foord, 1883, 

 Cont. to Micropalseon- 

 tology, p. 16, Tren- 

 ton Gr. 

 wincbelli, Ulricb, 1886, 14th Rep. Geo. 



Sur. Minn.,' p. 91, Trenton Gr. 

 ANISOTKYPA, Ulrich, 1883, Jour. Cin. Soc. 

 Nat. Hist., vol. 6, p. 275. [Ety. anisos, 

 unequal ; trupa, perforation.] Ramose, 

 hollow, inner side lined with an epi- 

 theca; walls of tubes thin in the in- 

 terior, and thickened exteriorly; no 

 interstitial cells or spiniform tubuli. 



FIG. 450. Am - 

 plexopora 

 robusta fun- 

 nel-s h a p ed 

 diaplirag m, 

 supposed to 

 be a modified 

 cystiphragm. 



Type A. symmetrica. 

 stulosa, U" 



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

 vol. 8, pi. 72, St. Louis Gr. 



rainulosa, Ulrich, (in press,) (Jeo. Sur. 

 111., vol. 8, pi. 72, St. Louis Gr. 



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

 vol. 8, pi. 72, Kaskaskia Gr. 



symmetrica, Ulrich, 1883, Jour. Cin. 

 Soc. Nat. Hist., vol. 6, p. 76, Kaskas- 

 kia Gr. 



ARCHIMEDES, LeSueur, 1842, (Retepora ar- 

 chimedes,) Am. Jour. Sci., vol. 43, p. 

 19. [Ety. from its resemblance to the 

 machine for raising water, consisting 

 of a tube rolled in a spiral form around 

 a cylinder, invented by Archimedes. 

 Distinguished from Fenestella by its 

 axis and mode of growth ; the flabel- 

 liform expansion acquiring a solid cen- 

 tral axis, around which it revolves in 

 an ascending spiral form, spreading 

 equally in all directions. Type A. 

 wortheni. 



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



111., vol. 8, pi. 63, Kaskaskia Gr. 

 compactus, Ulrich, 

 (in press), Geol. 

 Sur. 111., vol. 8, 

 pi. 63, Kaskaskia 

 Gr. 



distans, Ulrich. (in 



press), Geol. Sur. 



111., vol. 8, pi. 



63,KaskaskiaGr. 



grandis, Ulrich, 



(in press), Geol. 



Sur. 111., vol. 8, 



pi. 63, Keokuk 



Gr. 



intermedius, Ul- 



rich, (in press), **& 



Geol. Sur. 111., Fio. 451 Archimedes 

 vol. 8, pi. 63, reversus. 



Kaskaskia Gr. 



invaginatus, Ulrich, (in press), Geol. Sur. 

 111., vol 8, pi. 63, Kaskaskia Gr. 



laxus, Hall, 

 1857, Proc. 

 Am. Aes'n 

 Ad. Sci., 

 vol. 10, p. 

 176, Kas- 

 kaskia Gr. 



'M^ m Hall! n i857.' 

 Proc. Am. 

 Ass'n Ad. 

 Sci., vol. 10, 

 p. 176, Kas- 

 kaskia Gr. 

 negligens, Ul- 

 rich, (in 

 press), Geo. 

 Sur. 111., 

 vol. 8, pi. 

 63, Keokuk 

 Gr. 

 owenanus, Hall, 1857, Proc. Am. Ass'n 



Ad. Sci., vol. 10, p. 176, Keokuk Gr. 

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



111., vol. 8, pi. 63, Kaskaskia Gr. 

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



111., vol. 8, pi. 63, Kaskaskia Gr. 

 reversus, Hall, 1858, Geo. Rep. Iowa, p. 



652, Warsaw Gr. 

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



111., vol. 8, pi. 63, Kaskaskia Gr. 

 swallovanus, Hall, 1857, Proc. Am. Ass'n 

 Ad. Sci., vol. 10, p. 176, Kaskas- 

 kia Gr. 

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



111., vol. 8, pi. 63, Kaskaskia Gr. 

 wortheni, Hall, 1857, Proc. Am. Aes'n 

 Ad. Sci., vol. 10, p. 176, and Geo. Sur. 

 Iowa, p. 651, Warsaw Gr. 

 Archimedipora, D'Orb., 1850, Prod, de Pal., 

 t. 1, p. 102, syn. for Archimedes. 

 Archimedipora archimedes was too 

 tautological, and by common consent 

 Archimedes has become the generic 

 name. 

 archimedes, see Archimedes. 



FIG. 452 Archimedes 

 wortheui. 



