346 



BRA CHIOPODA. 



[ELK. KON. 



ELKANIA, Ford, 1886, Am. Jour. Sci. and 

 Arts, 3d ser., vol. 32, p. 325. [Ety. 

 proper name.] Shell thin, calcareous, 

 inarticulate, longitudinally ovate or sub- 

 circular, convex ; ventral valve, with 

 solid beak and minute-grooved area ; 

 muscular scars, six in each valve ; be- 

 neatb the rostrum a spoon-shaped pit 

 separates the scars. Type E. de- 

 siderata. 



desiderata. Billings, 1862, (Obolella desid- 

 erata,) Pal. Foss., vol. 1, p. 69, Up. 

 Taconic. 



EUMETRIA, Hall, 1864, 16th Rep. N. Y. 

 St. Mus. Nat. Hist., p. 59. Shell lon- 

 gitudinally Buboval ; striated, without 

 mesial fold and sinus ; structure punc- 

 tate ; beak of the ventral valve incurved ; 

 hinge area contracted ; foramen large; 

 internal spires as in Athyris ; dorsal 

 valve in the form of a pectinoid shell, 

 with diverging lamella*, which extend 

 beneath the cardinal area of the ventral 

 valve on either side of the center ; pro- 

 cesses extending into the cavity of the 

 dorsal valve, gradually converge, and 

 are united by a transverse concave 

 septum. Type E. vera. 

 prima, White, 1862, (Acambona prima,) 

 Proc. Bost. Soc. Nat. Hist, vol. 9, p. 27, 

 Burlington Gr. 



vera, Hall, 1858, (Retzia vera,) Geo. Sur. 

 Iowa, p. 704, Kaskaskia Gr. 



vera var. costata, Hall, 

 1858, (Retzia vera var. 

 costata,) Geo. Sur. Iowa, 

 p. 704, Kaskaskia Gr. 

 verneuilana, Hall, 1858, 

 (Retzia verneuilana,) 

 Trans. Alb. Inst, vol. 4, 



FIG. 566,-Eume- P- 19, and Geo. Sur. Iowa, 

 tria verneull- p. 657, Warsaw Gr. 

 ana - GLASSIA, Davidson, 1881, 



Lond. Geo. Mag., vol. 8, p. 11. [Ety. 

 proper name.] Shell ovate ; spiral coils 

 in the dorsal valve for the support of 

 the brachial appendages connected by 

 a loop as in Atrypa; lamellae converge 

 downward like the letter V, with the 

 extremities turned slightly upward be- 

 fore uniting ; principal coils face the 

 lateral margins; ends of the spirals 

 meet in the center of the shell ; spirals 

 consist of four or five compressed coils. 

 Type G. obovata. 



headi, Meek, 1873, (Zygospira headi,) 

 Ohio Pal., vol. 1, p. 127, Hud. Riv. Gr. 



Gonioccelia, Hall, syn. for Pentagonia. 



GYPIDULA, Hall, 1867, Pal. N. Y., vol. 4, p. 

 373. [Ety. gyps, vulture ; in allusion to 

 the strongly incurved beak.] Short, 

 gibbous or ventricose , ventral valve 

 muchjthe larger, with or without mesial 

 fold ; a large fissure, and elongate, much 

 incurved, trough-shaped pit ; dorsal 

 valve depressed in front ; area on both 

 valves, that of the ventral striated as in 

 Spirifera ; lamella? of dorsal valve sepa- 

 rate and diverging. Type G. occidentalis. 



I laeviuscula, Hall, 1867, Pal. N. Y., vol. 4, 

 p. 381, Devonian. 



munda, Calvin, 1878, Bull. U. S. Geo. 

 Sur., vol. 4, No. 3, p. 730, Low. Devo- 

 nian. 



obsolescent, see Pentamerella obsolescens. 



occidentalis, Hall, 1858, (Pentamerus oc- 

 cidentalis,) Geo. Rep. Iowa, vol. 1, pt. 

 2, p. 514, Ham. Gr. 



unguiformis, Ulrich, 1886, Cont. to Am. 



Pal., p. 28, Niagara Gr. 



Hemipronites, Pander, 1830. This name, 

 not having been defined, has been 

 superseded by Streptorhynchus, if the two 

 names refer to the same form. 



americanus, see Streptorhynchus ameri- 



canum. 



HINDELLA, Davidson, 1882, Monogr. Brit. 

 Foss., Brachiopoda, vol. 5, p. 130. [Ety. 

 proper name.] Shell elongate, ovate; 

 about six coils in each spiral; apices 

 directed laterally ; stems attached to the 

 hinge plate, and extending into the in- 

 terior, they are abruptly bent backward, 

 and then form a broad, rounded curve, 

 facing the bottom of the dorsal valve ; 

 when they reach the front they give 

 off a semicircular loop, having a spike- 

 like process at the top, directed toward 

 the beak. Type H. umbonata. 



umbonata, Billings, 1865, (Athyris um- 

 bonata,) Pal. Foss., vol. 1, p. 144, Mid. 

 Sil., Anticosti Div. 1. 



Hipparionyx, Vanuxem, 1842, Geo. 3d Dist. 

 N. Y., p. 124, syn. for Orthis. The 

 genus was founded on a cast. 



consimilis, syn. for Atrypa reticularis. 



proximus, see Orthis proximus. 



similaris, Vanuxem, 1842, Geo. Rep. 3d 

 Dist. N. Y., Oriskany sandstone. Not 

 defined. 



IPHIDEA, Billings, 1874, Pal. Foss., vol. 2, p. 

 76. [Ety. proper name.] Ventral valve 

 conical, elevated at the 

 beak, hinge-line nearly 

 straight, posterior angles 

 rounded, sides and front 

 nearly uniformly rounded ; 

 posterior side with a large ideabelfa. 

 false area and a convex 

 pseudodeltidium ; dorsal valve semi- 

 circular, moderately convex, most ele- 

 vated at the beak ; surface concentrically 

 marked. Typal. bella. 



bella, Billings, 1872, Can. Nat., vol. 6, p. 

 477, and Pal. Foss., vol. 2, p. 76, Up. 

 Taconic. 



sculptilis, see Kutorgina sculptilis. 

 KONINCKIA, Suess, 1853. MS. published by 

 Woodward, 1854, in Manual of Mol- 

 lusca, p. 231. [Ety. proper name.] 

 Shell circular, inequivalve, com- 

 pressed ; ventral valve convex, with 

 a slight longitudinal depression ; 

 beak incurved, with auricular expan- 

 sions ; dorsal valve concave ; surface 

 smooth ; no area or deltidium ; valves 

 inarticulated ; mesial ridge in dorsal 

 valve ; oral appendages supported by a 



