BRACHIOPODA. 277 



Genus MEGALANTERIS, Suess. 1855. 



PLATE LXXVII. 



1830. Terelnatula, de Verneuil. Bull. Sr c. G60I. jle France, 2 ser., vol. vii, p. 17.'>, pi. iv, %. 2. 



1855. Megmiteris, Sues.s. Ueber Meganteris ; Sitzungsbev. (lev Kais. Acad, der Wissen.sch. zu Wieii. 



1856. Mugantms, iSusss. Cla.ssitication der Brachiopoden, von Th. David.son, p. 43, pi. ii, fig. 18. 

 18.o7. MegaJdorix, Hall. Tenth Ann. Kept N. Y. State Cab. Nat. Hist., p. 101. 



1859. Jienssilcerla, Hall. Palaeontology of New York, vol. iii, p. 458, pi. cvi, tijf. 2o-/. 



1861. lioissclceria, McChesney. Descr. New Fossils from Palaeozoic Rocks of West. Stales, p. 85. 



1867. Rensselmrla, McChesnet. Trans. Chicago Acad. Sciences, vol. i, p. 36, pi. vii, figs. 2a-c. 



1868. Renxselmria, Meek and Worthen. Geological Survey of Illinois, vol. iii, p. 401, pi. viii, figs. 4 a, b. 

 1871. Meganteris, Quenstedt. Petrefactenkunde Deutschlands ; Brachiopoden, p. 344, pi. xlvii, 



figs. 21, 22. 

 1876. Meganteris, F. Roemer. Lethoea Pala=ozoica, j)!. xxiii, iig. 6. 

 1887. Megalavtcris, (Ehlert. Fischer's Manuel de Condiyliologie, p. I3I!1. 

 1891. Ntwbeniaf, Hall. Tenth Rept. N. Y. State Geologist, p. 95. 



Though this generic division is of long standing, its value has been regarded 

 as somewhat uncertain. Sliells agreeing with the type of Megalanteris in 

 external form and in the conformation of the interior of the valves are not of 

 uncommon occurrence ; but these are so closely allied to RENSSELiERiA in exter- 

 nal form, that the possession by them of a brachidium widely dissimilar to the 

 corresponding apparatus of that genus seems a priori improbable. The ideal- 

 ized restoration of this structure, given by Suess, has not been confirmed by 

 later investigations, but neither has it been disproved ; and we are therefore 

 justified in assuming its accuracy. The American species, M. ovalis, Hall, is 

 not favorably preserved for the retention of those parts. 



To apprehend the author's conception of this genus, a translation of the 

 diagnosis inserted in his edition of Davidson's " Classification of the Brachiopoda " 

 is here introduced : 



" Shell, in the only species hitherto known, large, smooth, equally biconvex, 

 of very variable, elongate-hexagonal to transversely oval outline, and with 

 punctated shell structure. Beak depressed, with a small opening for the pedicle- 

 muscle, reaching to the somewhat incurved umbo of the pedicle-valve and 

 limited on both sides by a depressed deltidium. Hinge apparatus strong, 

 similar to that of other terebratuloids. Below the beak of the dorsal valve, 

 the central part of the hinge-j^late is swollen into a callous uncinate process, 

 which is subcubical, and on its surface bears two small V-shaped ridges for the 



