1904.] NATURAL SCIENCES OF PHILADELPHIA. 411 



EUCOXULUS TURBIXATUS. I 



ZONITOIDES BRISTOLI. j 



Vertigo numellata. I" Eastern North America. 



" MARKI. I 



Carychium bermudense. J 



^ZoNiTOiDES minusculus. North America and West Indies. 



^BiFiDARiA RUPicoLA. Florida, Cuba. 



^Strobilops hubbardi. Florida, Jamaica. 



Thysanophora hypolepta. West Indies. 



SucciNEA bermudensis. West Indies. 



Total, 17 forms, 14 of them probably peculiar to Bermuda. For 

 comparison we have the following recent species,' supposedly not im- 

 ported by man : 



Pcecilozonites bermudensis, ] 



" reinianus, i 



circumfirmatus, I Remnant of the fossil fauna. 



^Zonitoides minusculus, f- Seven species. 



Thysanophora hypolepta, 



succinea bermudensis, | 



^BiFIDARIA RUPICOLA. J 



"PupoiDES MARGiNATUs. North America, West Indies. 



^Thysanophora vortex, ] 



tolygyra microdonta, 



•'^BiFiDARiA SERViLis, \ West Indies. Five species. 



^BlFIDARIA JAMAICENSIS, I 



I 



Helicixa coxvexa. J 



Total, 13 species, 6 of them probably pecuhar to Bermuda. 



Dr. Pilsbry's conclusion, from the anatomy of Pcecilozonites, that the 

 oldest importations to Bermuda came from continental America, is thus 

 confirmed by a large maj ority of the fossil forms. Bermuda, at the time 

 of the No. 807 deposit, was characterized by not less than five genera 

 of continental affinities, of which at least one had been resident long 

 enough to have developed new generic characters and a respectable 

 diversity of species. The abundance of the individuals, too, and the 

 size and variability of some of the species, seem to show that the island 

 was not inhospital^le to continental genera at that epoch. There were 

 not only the large extinct species Pcecilozonites nelsoni and Pcecilozo- 

 nites cupula, but larger varieties also of Pcecilozonites hermuclensis and 



* Species not peculiar to Bermuda. 



* Species not peculiar to Bermuda. 



