CONCHOLOGY. 31 



P. Aldrovandi. The Panopasa of Aldrovandus. PL 5, 



The type of this genns, transversely elongated, undulated ; 

 concentrically wrinkled ; of dark green colour, alnaost black. 



3. Solecurtus. Three species. 



Shell oval, elongated, equivalve, sub-equilateral, edges al- 

 most straight and parallel ; the extremities equally rounded, 

 and as if truncated ; summits but little marked ; hinge tooth- 

 less, or formed by some rudimentary primary teeth ; ligament 

 projecting, affixed to the thick nymphal callosities ; two dis- 

 tant, rounded muscular impressions. 



Solecurtus radiatus. Solecurtus strigilatus. 



S. legumen. 



S. radiatus. The radiated Solecurtus. 

 Species flat, small, with an interior ridge running down 

 obliquely from the summit to the abdominal margin. 



S. strigilatus. The strigilated Solecurtus. 

 Species more cylindrical, without interior ridge, 



S. legumen. The Pease-pod Solecurtus. PI. 31, fig. 6. 

 Species still more elongated and sub-cylindrical. 



4. Glycimeris, Two species. 



Distinguished from the Solen by being without teeth at 

 the hinge. 



Shell covered with epidermis, slightly irregular, elongated, 

 gaping at the two extremities, equivalve, inequilateral ; the 

 summits but little marked ; hinge toothless ; a longitudinal 

 callosity ; ligament exterior, affixed to very projecting cal- 

 losities on the shortest side of the shell ; two distinct mus- 

 cular impressions. 



Glycimeris margaritacea. Glycimeris siliqua. 



G. siliqua. The podlike Glycimeris. 



Transversely oblong, covered with a black epidermis ; 



