NO. 5 RHYNCHONELLOID BRACHIOPODS — COOPER IJ 



Sphenarina. — Deltidial plates conjunct; subequivalve ; brachial valve with no 

 median ridge ; slight or no development of inner hinge plates. 



Erymnariidae Cooper, new family. — Rhynchonelloidea having sep- 

 tifer crura. 

 Genus : Erymnaria. 



Erymnaria. — Exterior smooth, inequivalve ; anterior commissure uniplicate 

 to twisted; deltidial plates conjunct; the brachial valve having the greater depth. 



Family Cryptoporidae Muir-Wood 1955 



Genus CRYPTOPORA Jeffreys, 1869 



Plates 1, A, B, 2, A, 5, C, 21, D; text figure iA 



Cryptopora Jeffreys, Nature, vol. 1, p. 136, 1869 (inadequately described, not 



figured) ; Thomson, Geol. Mag., n. s., dec. 6, vol. 2, pp. 387, 388, 392, 1915; 



Thomson, New Zealand Board Sci. Art, Manual 7, p. 146, 1927. 

 Atretia Jeffreys, Proc. Roy. Soc, vol. 18, No. 121, p. 421, 1870 (inadequately 



described, not figured) ; Ann. Mag. Nat. Hist., ser. 4, vol. 18, p. 250, 1876 ; 



Proc. Zool. Soc. London, p. 412, 1878 ; Davidson, Trans. Linnaean Soc, ser. 2, 



vol. 4, pt. 2, p. 173, 1887. Not Atrethtm Cope, 1861. 

 Neatretia Fischer and Oehlert, Exped. Sci. Travailleur et Talisman, p. 122, 1891. 

 Mannia Davidson, Geol. Mag., dec. 2, vol. 1, No. 4, p. 156, 1874(b). 



Small, translucent to transparent, subtriangular in outline with the 

 greatest shell width anterior to the middle; subequivalve; anterior 

 commissure rectimarginate to broadly sulcate ; surface smooth. Beak 

 of the pedicle valve moderately long, pointed, nearly straight ; foramen 

 large, incomplete, not restricted ; deltidial plates rudimentary, forming 

 a ridge on the delthyrial edge, auriculate to alate. Shell fiber mosaic 

 coarse. 



Pedicle valve interior with small noncorrugated teeth; apex with 

 thickened plate elevated above valve floor ; teeth supported by strong, 

 divergent dental plates. Muscle scars not well impressed. 



Brachial valve interior with small, smooth or roughened sockets 

 bounded by high socket ridges ; socket ridge overlying crural base ; 

 crura of maniculifer type, long and slender, slightly curved, expanded 

 distally and commonly with the distal edge deeply digitate. Cardinal 

 process small, bilobed and transverse. Median septum high anteriorly 

 but sloping steeply to the valve floor posteriorly and disappearing an- 

 terior to the apex; anterior face of septum steep. Adductor scars 

 lightly impressed. One pair of metanephridia in the fleshy body of 

 the animal. 



Type species (by monotypy). — Atretia gnomon Jeffreys. Ann. 

 Mag. Nat. Hist., ser. 4, vol. 18, p. 251, 1876. 



