CLASS I 



PELECYPODA 



483 



with tlie smooth Ijaiuls of Badiolites, and indicate the position of the siphons. 

 Woodward supposes that the pit (;/;) contained the internal ligament ; but so far, 



Hipiiwrites dosavknsis 

 Douv. Upper Cretace- 

 ous ; Gosaii Valley, 

 Austria, i/o. 



HippurUes opiidl Douville. Nefgraben, near Russ- 

 bacii, Salzburg. A, B, C, Impressed lines bounding 

 convex vertical areas (columns) corresponding to the 

 region of the hinge. 1/2. 



HippurUes orf/anisans 

 Montf. Vertical section 

 of a valve below tlie 

 living chamber, show- 

 ing the septa and inter- 

 septal cavities of the 

 middle layer, i/j. 



remains of the ligament have only been found in the l)ottom of the outer anterior 

 sulcus, where it seemed to form a vertical band. The second adductor scar is small, 

 and located between the sulcus and the anterior column {B). The clithrum of the 



Fin. 785. 



Hiiiinirites radiosus T>e&m. Upper Cretaceous (Dordonian) ; Royan, Charente. a, Upper valve (.1, Sinus of 

 the hinge ; B, .C, Grooves corresponding to anterior and posterior columns of the lower valve ; c, Anterior, and 

 c', c", Posterior processes of the clithrum). b, Interior of lower valve seen from above (A, Sinus ; B, C, Posi- 

 tion of anterior and posterior columns ; a, a', Adductor scars ; d, Socket of anterior, and d', d", of posterior 

 processes of clithriuu ; u. Body chamber of shell ; x, Vacant cavity near the sinus). 2/^ (after liayle). 



upper valve is extremely difficult to prepare, and is known in only a few species. 

 The anterior process shows near its base two tubercles {a, a'), which correspond to 



