DR. P. P. CARPENTER ON NEW MOLLTJSCA. H 



natis, postice divergentibus, striis incrementi crebris acutis, 

 aliter hand sculpta ; parte antica t. jun. aperta, adultm clavsa ; 

 clausis tenuissimis, secundum incrementa undulatis, super um- 

 bones prolongatis, umbilicos postice formantibus ; epidermide 

 fugaci, tenui, pallide viridi. 

 Hab. Monterey, Rich,.; Vancouver, Lord; S. Diego, Cooper, 

 = Pholas darwinii, Sby. 

 = Joiianetlia darwinii, Mus. Cuming.- 

 = Parapholas penita, Tryon, Mon. Phol. 



This remarkable shell differs from Jouanettia in having both 

 valves equal ; from Pholadidea proper in having no coriaceous 

 cup, its place being supplied by a flattened prolongation from 

 each valve, like a duck's bill in miniature. In Mr. Lord's specimen 

 (preserved in the British Museum), though the valves are closed, the 

 ^ prolongations are widely divergent, as when the bird utters its cheer- 

 ful " quack." The loose, thin epidermis appears to have covered the 

 bill as well as the valves. Mr. Tryon had probably not seen a speci- 

 men, else he could hardly have affiliated so very different a shell to 

 Pholadidea penita. The original specimen is said to have come from 

 Chili. 



DaRINA DECLIVIS. 



D. t. tenuissima, planata, elliptica, MacheBraformiyUtroque latere 

 hiante ; cinerea, epidermide fortiore induta ; marginibus regu- 

 lariter excurvatis ; umbonibus haud conspicuis, ad duas inter 

 quinque partes longitudinis postice sitis : intus cartilagine 

 spathula elongata, dorsum versus utraque valva decliviter sita, 

 a Hgamento lamina extante tenuissima separata; dente car- 

 dinali laminato, extante, curtiore ; lateralihus vix conspicuis ; 

 sinu pallii ovali, fere ad medium porrecto. 

 Long. 1-77, lat, -85, alt. -34 poll. 

 Ilab. Vancouver's Island (Forbes). 



The only other species of Barina known is from the Straits of 

 Maghellan. The northern shell may have been passed over as the 

 young of Machcera patula, to which it bears a strong external re- 

 semblance. 



Saxidomus brevisiphonatus. 



S. t. subovali, tenuiore, subplanata, albida, epidermide pallide 

 olivaeea induta; tota superflcie rugis concentricis, crebris, 

 valde obtusis, et undis incrementi interdum majoribus, ornata ; 

 marginibus submqualiter excurvatis, maxime ventrali ; intus 

 cardine tenuiore, dente antico elongata ; sinu pallii parvo, ad 

 trientem interstitii porrecto, latiore. 

 Long. 2-65, lat. 2-05, alt. MS poll. 

 Hab. ?Vancouver, ?Japan (Mus. Cuming"). 

 A very distinct species, in shape and hinge not unlike Callista, but 

 without lunule. It is more rounded and flatter than the three ty- 

 pical Californian species, and known at once by the very small mantle- 

 bend. From four to six blunt riblets are seen on each of the very 



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