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PALAEONTOLOGY OF NEW YORK. 
Genus OLDHAMINA, Waagen. 1883. 
1863. Bellerophon, db Koninck. Quart. Jour. Geol. Soc. London, vol. xix, p. 8. 
1880. Thecidea, Zugmayer. Unters. liber rhat. Brachiopoden; Beitr. zur Palaont. Oesterreich- 
Ung-arn, I, p. 22. 
1883. Oldhamina, Waagen. Productus-limestone Fossils; Brachiopoda, pp. 403-409, pi. xxxi, figs. 1-9. 
Shells highly concavo-convex. 
Pedicle-valve subhemispherical; apex incurved, at maturity covered by a 
callosity, as in Bellerophon ; attached by cementation in early growth. Hinge¬ 
line short and straight, not interrupted in the middle; below it lie well- 
developed teeth. Interior surface of the valve covered with diverging lateral 
ridges. 
Fig. 247. 
Fiff. 245. The exterior of a pedicle-valve with the shell partly exfoliated. 
Fig. 246. Posterior view of the brachial valve; showing elevation and lobation of the cardinal process. 
Fig. 247. The interior of a pedicle-valve; showing the median and lateral ridges. (Waagen.) 
Brachial valve concave. Cardinal process inconspicuous, quadripartite at the 
summit; continuous with a median ridge extending the entire length of the 
valve. Internal surface covered with divergent grooves corresponding to the 
ridges of the opposite valve. 
Exterior smooth or with numerous concentric lines of growth. 
Type, Oldhamina decipiens, de Koninck. Carboniferous. India and China. 
Dr. Waagen has described the structure of these genera at great length, and 
from his investigations infers that the shells are not distantly related to 
