ORDER I PRIONODESMACEA 383 
digitiform, usually byssiferous, the byssus passing through the gape of the valves. 
Carboniferous to Recent. 
Lima, Brug. Shell inflated, with radial sculpture ; beaks pointed, and separated 
by a lozenge-shaped area; edentulous. Carboniferous to Recent ; 
maximum in Mesozoic (over 300 
species). 




Sub-genera: Lima s. s. (Radula, 
auct. non Gray), (Fig. 671). Shell with 
strong radial ribs. 

Fic. 673. 
Lima (Limatula) 
gibbosa, Sow. 
Lower Oolite; 
Bayeux, Calvados. 


y 
NTH 
DOM } H 
K SNA i 1 
Z 



Fic. 674. 
Limaea duplicata, 
Goldf. Great 
Fic. 671. 
A PA re =, Fie. 672. 
Lima vectinoides Sow. E 
£ ; 
Lower Lias ; Balingen, Wur- Lima (Plagiostoma) gigantea, Sow. Lower Lias; Oolite; Langrune, 
temberg. 1/3. Goéppingen, Wurtemberg. 2/3. Normandy. 
Plagiostoma, Sow. (Fig. 672). Smooth or finely striated. 
Limatula, Wood (Fig. 673). Medially ribbed, laterally smooth, valves not gaping. 
}e 
KC 
2 =Ss 
AS 
Ce 
WG 
7 
KG 

Fic. 675. 
Ctenostreon proboscidea, Sow. Oxfordian ; Dives, Calvados. 
Limaea, Bronn (Fig. 674). Small, with Taxodont armature at the angles of the 
hinge. Lias and Recent. 
Ctenostreon, Eichw. (Fig. 675). Compressed, irregular, thick-shelled, with coarse 
radial ribs. Upper Jura. 
