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SHELL GALLERY. 
curved plates on the brachial and a ridge on the peduncle valve, 
is found on the American coast of the Pacific, and in the Atlantic. 
Order 2. — Neotremata. The Discinidm includes two genera, 
Distinct, and Discinisca (Fig. 7), with orbicular conical shells, of 
horny calcareous composition ; both valves are conical in the former 
Fig. 7. 
Discinisca lamellosa. Peru. (After G. Sowerby.) 
A group of old and young specimens ; largest showing foramen in peduncle 
valve, the rest showing brachial valves. 
genus, but in the latter the peduncle valve is flattened. Sometimes 
the embryos settle down on the parent shells, and we see a mass of 
shells in various stages of growth, as in the specimen of Discinisca 
lamellosa from Peru. 
The Graniidw form small limpet-like shells (Fig. 8) closely 
adherent to the rocks by the whole surface of the peduncle valve ; 
Fig. 8. 
Wm&p 
Three specimens of Crania anomala on a stone. Loch Fyne. 
although this valve is so named, no peduncle or foramen is found in 
this family. The Neotremata, like the Lingulida, are remarkable 
