280 CEETACEOUS PELECYPODA 



23. Goodalliopsis, Rain, et M. -Chalmers, ISGS, (Journ. de Concliil., p. 194), 

 Shell similar to Goodallia, but the hinge has two cardinal and one distinct, 

 elongated posterior lateral tooth in each valve ; the authors of the genus simply 

 say, dentibus lateralibus elongatis, prominentibus, which may mean that both 

 anterior and posterior lateral teeth are present, but the figure of the hinge does not 

 show any anterior lateral teeth. The type species, G. Orbignyi, is from the eocene 

 beds near Eercourt. 



24. Woodia, Desh., 1860, (Paris foss., 2nd edit., i, p. 790). Shell sub- 

 orbicular, with obtuse beaks, slightly tumescent, margins internally crenuiated ; 

 hinge with one large grooved cardinal tooth in the right and two diverging teeth 

 in the left valve ; sometimes with small sub-obsolete lateral teeth close to the 

 cardinal. Type, W, digataria, L., from the Mediterranean. Deshayes describes 

 three eocene species from the Paris basin. The genus appears to differ from 

 Goodallia only by its more rounded shape and internally crenated margins, the 

 hinge being in both very similar. 



b. 8uh-family,~-CABBITINM. 



25. Matheria, Billings, 1858. Shell elongated like Fleurophorus, concen- 

 trically striated, beaks anterior, hinge of left valve with two, of the right with one 

 small cardinal tooth ; type, M, tenera, Bill., from the Trenton group of Canada, 

 (see GeoL, Canada, vol. i, p. 147). 



26. FletiropJwrus, King, 1848, (Perm, foss., p. 180). Shell elongated, 

 very inequilateral, moderately tumid, posterior surface radiately ribbed; hinge 

 with two radiating cardinal, and one posterior lateral tooth in each valve; 

 anterior muscular impression very deep with a small superimposed pit. Type, 

 JP, costatus, Brown, sp. King mentions that the triassic Cardita crenata, Goldf., 

 also belongs to this genus, but its cardinal teeth are more similarly formed to those 

 of Cardita than to the type of Fleurophorus, and the species, therefore, is rather 

 referable to the next genus. 



27. Falcsocardiia, Con., 1867, (Am. Journ. Conch., iii, p. 11). Shell elon^ 

 gately trapezoid, inequilateral, moderately inflated, radiately ribbed; hinge with 

 two blunt cardinal teeth and one posterior lateral tooth in each valve. Conrad 

 proposed this genus for the triassic Cardium austriacum, Hauer, {Cardita id, apud 

 Stoppani), but the better known Cassian Cardita crenata may rather be considered 

 as the type of the genus. The principal cardinal tooth is thick and blunt, formed 

 exactly as in Cardita, and what is termed anterior cardinal is, strictly speaking, 

 a sub-lunular tooth, and could with equal propriety be called anterior lateral. I 

 believe that to this genus should also be referred a great number of cretaceous 

 CarditcB of the type of C JDupiniana, d'Orb. I have seen small specimens of 

 this species without a trace of a lateral tooth, but one large specimen in our 

 collection has a small, though distinct, posterior lateral. These cretaceous 

 CarditcB, or MytilicardicB, mostly differ from the recent species of the last genus 

 by the want of an anterior insinuation of the ventral margin, where in true 



