DR. P. P. CARPENTER ON NEW MOLLVSCA. 



nntis, posfice (liceryenfihus, stri'is incrementi crebris acufis, 

 aliter lunul snifiitd ; partu uiitica t.jun. ajjeita, adultce rfuvsa ; 

 clausis teiiuiiS)iiitiis, seciuulum incrementa undulatis, super mn- 

 bones prolonyatln, intift'tlivos postice furmantibus ; epU/tnnit/e 

 /'uf/aci, tenui, ptilliile viriili. 

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

 = Phulas dfiririiiii, Sl)v. 

 s= Jouanettia dancinii, Mus. Cuming. 

 ^ Parajiholas penita, Tryon, Mon. I'hol. 



This remarkable sluU iliffers from Jouanettia in having both 

 valves equal ; from Pholadidea proper in having no coriaceous 

 cup, its place being supi>lied 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 •' quai'k." The loose, thin epidermis appears to have covered the 

 bill as well as the valves. Mr. 'I'ryon 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. tenuinsima, planata, elliptica, Machcerceformi, utroque latere 

 hiante ; cinerea, epideriiiide fortiore induta ; martjinibus reyu- 

 lariter excurvatis ; ntnbonibus haud conspicids, ad duas inter 

 quinque partes lonyititdinis postice sitis : intus cartilayine 

 spathula elonyatu, dorsum versus utraque talva decUviter sita, 

 a lif/amento lamina extatite tenuissima separata; dente car- 

 dinali lanilnato, extante, curtiore ; lateralibus vix conspicuis ; 

 sinu pallii ovali, fere ad medium por recto. 

 Long. \'~7, lat. •'6'>, alt. •;^4 poll. 

 ITab. Vancouver's Island {Forbes). 



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

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

 young of Macheera putula, to which it bears a strong external re- 

 semblance. 



Saxidomus brevisifiionatus. 



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

 olivacea induta ; fata superjicie rut/is concentricis, crebris, 

 valde obtusis, et uiidis incrementi iuterdum majoribus, ornata ; 

 marginibus subaqnalitcr excurvatis, maxime ventrali : intus 

 curdine tenuiore, dente anrico elonyato ; sinu pallii parco, ad 

 trientem interstitii porrecto, latiore. 

 Long. 2().>, lat, 'J-O.i, alt. l-l.") poll. 

 Hub. ?Vancouver, ?Japan (Mus. Cuming). 



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

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

 pical Californian .--pecies, and known at once by the very sm.iU mantle- 

 beuJ. From fotr to six blunt riblets are seen ou each of the very 



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