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Page. 



Fig. 1. Tellina scitula 197 



1, «. A dorsal view of the two valves united and partly open (type). 



1, 6." Right-side view of tbe same, with the shell partly removed, so as to expose partly tho 

 internal cast. 



Fig. 2. Linearia? Formosa 199 



A right-side external view of a valve attached to a piece of rock (type-specimeu). 

 Fig. 3. Ne.eka ventuicqsa 238 



3, a. Left side of the perfect type-specimen, natural size. 



3, 6. Dorsal view of same. 



3 c. Left exterior view magnified. 



3, d. Interior aud hiuge views of a right valve, natural size 



3, e. The same, magnified. 



Figs. 4 and 1, b (bis). Corbula inornata 245 



4,<i. Left view of the type-specimen, with the two valves united (natural size). 

 1,6 (bis). A right-side view of same, magnified. 



4, c. Leftside, with valves united, magnified about two diameters. 



4, d. A posterior view of the two valves united, magnified as above. 



Fig. 5. Veniklla humilis 155 



5, a. Anterior view of the type-specimen, consisting of the two valves united, but exfoliated 



about the beaks. [The spiral appearance of one of the beaks of this figure is not 

 natural.] 

 5, b. A side view of same. 



5, c. An internal cast of same species, showing muscular and pallial impressions. 



Fig. 0. Mactra ? nitidula • 211 



6, o. A right-side view of type. [Margin slightly too much truncated behind.] 

 (1, b. An under or ventral side view of the valves united. 



6, i . Dorsal view of same. 



Fig. 7. Mactra Warrenana 208 



7,«. A left view of the perfect type-specimen, adult size. 



7, b. An anterior view of same. [Lunule represented too small.] 

 7,c. A posterior view. 



7, </. Lett side of an internal east, showing the muscular aud pallial impressions. 



Fig. 8. Martesia cuneata 259 



8, a. Left-side view, natural size (type-specimen). 

 8,6. An opposite view of same, magnified. 



Fig. 9. Turnus Stimpsoni 250 



9, a. An internal cast, natural size. 



9,6. Exterior of left valve, magnified (type-specimen). 

 Fig. 10. Turnus (Xvi.opiiaghi.la) ei.egantila 257 



10, a. Left side of an interval east, natural size (type-specimen). 

 10,6. Same view of exterior, magnified. 



10, c. A magnified anterior view. 



10, d. A less magnified posterior view of the two valves united, showing them to be closed 



behind. 

 10, e. A side view of an internal cast, magnified. 

 10,/. Posterior view of same. 



Fig. ll. Cyprina ovata, var. compressa 1 17 



An internal cast of a right valve (with some fragments of the shell attached), showing 

 muscular and pallial impressions (type of the variety). 



Fig. 12. Goniomya Americana ■_'■.' I 



12, a. The imperfect type-specimeu, left-side view. [Some of the basal as well as the postel ior 



margin seems to have been broken away.] 

 12, h. Granules of the surface, magnified. 



Fig. 13. Teredo GLOBOSA 204 



Burrows in fossil wood. 



•This figure occupies the light upper corner of tbe p'atc, and shoul.l not b'J confounded with another figure accidentally 

 muni erod 1, U on tin- same 



