62 
ROOM VIII. 
Nat. Hist. 
been found of 500 pounds weight. Part of the 
genus Modiola (Mytilus. Linn.), of the family 
of the Myiilacea, are contained in this compart¬ 
ment ; and the genera Mytilus (the muscle) 
and Pinna. 
Table 13. The family Malleacea^ and part 
of the Fectenida ; including under the former, 
the genera Crenatula (rather rare shells), Perna, 
Malleus (the two last classed as Oysters by Lin- 
nseus), Avicula (Mytilus. Lin.), and Meleagrina. 
The Meleagrina margaritifera (Mytilus margari- 
tiferus, Lin.) affords valuable pearls, and the in¬ 
side is formed of the beautiful substance known 
by the name of Mother of Pearl. Under the 
Fectenida, are included the genera, Pedum, con¬ 
taining only one species, P. Spondyloideum 
(Ostrea spondyloidea. Gmel.), Lima, Plagiosto- 
ma (fossil), and Pecten, or Scallop shell. The 
Lima and Pecten were considered as Ostrese by 
Linngeus. 
Table 14. Pecten continued ; and the genera 
Plicatula and Spondylus, or hinged Oyster. 
Table 1,5. Ostracea, including the genera 
Gryphaea (only one recent species of this genus, 
G. angulata, is known) ; Ostrea, Vulsella, and 
Placuna. 
Table 16. Anomia, the last genus of the 
Ostracea. Also the families Rudista, and Bra- 
chiopoda. In the first, are the fossil genera 
Radiolites and Calceola, and the recent genus 
Crania 5 in the latter the genera Orbicula, Tere- 
bratula (Anomia of Linnaeus), and Lingula. Of 
this 
