BRACHIOPODA. 



347 



Kutorga.) — Shell subcorneal, free, regular, depressed, 

 suborbicular, equilateral ; the bosses are scarcely terminal, 

 prominent, inequivalve ; the boss of the superior valve more 

 projecting, and provided within, with a strong channel for 

 the insertion of the peduncle ; the other valve is shorter, 

 and has no internal channel ; no hinge, the valves being 

 held together by the muscle. — Fossil. 



Order III. 

 EUDIST2E. 



The animals of this order are unknown. The shells are 

 bivalve, inequivalve, without a hinge, attached ; of a 

 peculiar cellular porous structure, on their inner surface ; 

 provided with peculiar moulds and impressions which are 

 difficult to describe. 



Family 1 . — RADIO LI TIDJE. 



The under valve is more or less cone-shaped, firmly 

 attached, of a cellular or fibrous structure; the upper valve 

 conical, or spirally wound, and free. 



Radiolites. Lam. (Sphoerulites La Meth. ; Acardo 

 Brug.) — Shell composed of two valves, which do not unite 

 at the edges of their bases, but of which the longer and 

 larger envelopes the other, and the dorsal disk of each is 

 elevated into the form of a nearly straight cone, slightly 

 arched interiorly: these horn-shaped valves are unequal, 

 and diverge obliquely in the form of the letter V, whose 



