DR. P. P. CARPENTER ON THE SHELLS OF PANAMA. 3 



10. Cypra'a radkms-=Trh'ia r., ISI. 440. 



1 1. Cyprtea i-uhescens-=^(\faA sp. of Trivia sanguinea, M. 442. 



12. Cyprcea sanguinea=Trivia s., M. 442. 



13. Erato scahriuscvla. Stet. 



14. Maryinalla minor. Stet, M. 587. 



1 7>. MoryineUa sapoiilla. The Panama specimens collected by 

 Prof. Adams, and almndantly by otbers, moie closely resemble M. 

 prmmm tlian the type M. sajjofilla of Hinds, which is a much smaller 

 shell. The Caribbean shells (which are found across the Isthmus 

 at Aspinwall) differ only in having a sharper angle in the labrum at 

 the posterior notch. Adanson's habitat, doubted by Prof. Adams 

 (note, p. 41), is confirmed by specimens in the Bristol Institution 

 brought from Sierra Leone by Chief Justice Kankine. The Pacific 

 shells are probably conspecific, sufficient evidence being now in our 

 possession that the two oceans were united at least as late as the 

 Miocene epoch*. 



16. MifrafimicuJata. Stet. 



17. Mitra lens, M. 585. 



18. Mitra nucleola. Closely resembling young specimens of the 

 Caribbean M. granulosa. 



19. Mitra snlitaria, CB. Ad. = Zierliana s. Other specimens 

 have since been found of this characteristic species. The "trans- 

 verse ribs" can scarcely be said to be "obsolete anteriorly." 



20. 3Iifra tristis = Sfrigatella t., M. 586. 



21. Terehra elata^Myurella e. 



22. Terehra larvceformis = Myurella L 



23. 24. Stent. 



25. Terehra tuberculosa = Myurella t. 



26. Terehra varicosa. This may possibly be a very young speci- 

 men of Subula V. ; but I think it distinct. 



27-31. Sp. ind. A specimen of Euryfa falyurata, M. 455, is in 

 the museum, as from Panama, but not of Prof. Adams's collecting. 



32. Olica angulata, M. 590. 



* The specimens in the Cumingian Museum, named M. ccerulescens at the time 

 of the British Association Report, are now labelled " sapotilla, Hds., 5-13 fathoms 

 sandy mud, Panama, H. C." Another set of Pacific shells (notch-angle rounded) 

 are given as ^' Marginella n. s., Panama," "San Domingo" having been erased. 

 The large West Indian form (notch-angle sharp) is given as '^ cofrulesceiis, vat.. 

 Lam., 10 fathoms sandy mud, Panama " Another set of large shells, with sharp 

 angle, and lahrum tinted behind, is given as " ctsrulescens, Lara., Panama," but 

 Without authority. The small West-Indian form (like the typical sapoiilla) is 

 given as " i/lam, Mke." Either in this, as in other instances, error has crept into 

 the locality-marks, or else even the distinction pointed out by Mr. Redfield (vrho 

 has given penuliar study to this geuus) cauuot be relied ou tor se^aiaung the spe- 

 01 s g.iL'graph' ally, 



12 177 



