90 



Notes on Species of Corhiculadce. 



The ligament is I0112: and narrow and somewhat concealed. The 

 strire are coarse and indistinct. The epidermis is brownish 

 green, without polish. The interior is w r hite. The hinge is 

 somewhat curved, not very broad, but strong. The cardinal 

 teeth are narrow and divergent, the two principal teeth are 

 bifurcated. The lateral teeth are short and obtuse. 



This species is somewhat allied to Gyrena Cyprinoides, it is 

 however more transverse, less trigonal, and the beaks are less 

 inflated. Compared with Gyrena similis, it is less heavy, more 

 orbicular, and somewhat more inflated. 



6. Cyrena regula&*is, Prime. 



Cyrena regularis, Prime. Acad. N. S. Phil. Proc. 136. 1861. 

 Prime Cat. 6. 1863. 



C. testa transversa, ovato-rotundata, valde inequilateral)', in medio 



Fig. 38. 



Cyrena regularis. 



subinflata ; latere antico, producto, angusto, rotund ato, postico subtrun 



