232 
NEW FOSSIL SHELLS 
Genera. No. of species, Genera, No, of species. Genera, No. of species. 
Marginella, , +s Patella, . fag Serpula, . gd 
Melongena, 3 Pecten, r ; 92 Sigaretus, ght 
Mitra, , : - op Pectunculus, . 22 Siliquaria, 2 
Modiola, : 2 Perna, i ial Solarium, 18 
Monodonta, 1 Petaloconchus, 1 Solen, 2 
Monoceros, 5 Petricola, 3 Solecurtis, 4 2 
Monoptygma,  . 2 Pholadomya, . Hae Spirorbis, ei 
Murex, . ; 6 Pholas, ; 5 Stalagmium, 1 
Mya, . 3 Placuna, . wee Strigilla, . ihe 
Myoparo, 1 Plagiostoma, 1 ge 
Mysia, 2 ‘Planaria, , ? eh q ellina, 9 
Mytilus, . 2 Pleurotoma, 32 7 erebra, : : 8 
J Plicatula, 4 Teretlo, : oe ie ® 
Nassa, : ; ad, Proto, I Thracia, ; i : oi 
Natica, : E é PERS Peammobia, 9, Triton, ' : Oe 1 
Nautilus, , eae 1 Pacenmocola; : pwgal ig Trochue; ‘ j ‘ 6 
Mogul 25 vedi uc jut ddd Ppeiiniag wads okt pape, een o des? neoirt 2 
Nummulites, 1 Pyrula, : 9 J Unbinelle, . ‘ ree 
Turritella, . - a RO 
Oliva, '. : 3 . LG Typhis, . j 3 po, 
Orbicula, . : oe l Ranella, . i ri E ] yI 
Orbis, . 3 : «wei Rostellaria, . , cogs Venericardia, 3 ef 
Ostrea, ji . 3 EO Rotella, . : : » 5 Venerupis, ' é : 
Venus, ; Peace | 
Pandora," : , nore Saxicava, >. r Fac jak Vermetus, ? : apt, 
Panopea, . ‘ iy ae Sanguinolaria, . i eon Voluta, ; : a 
Pasithea, : * ge a Scalaria, . . - + 16 | Volvaria,. ; ; ‘gen 
It is to the kindness of Mr. Tuomey, of Petersburg, that I owe the following shells, 
as well as those in the list a few pages back. Most of the smaller species herein 
described, I met with by carefully examining the sand scraped from the cavities of larger 
shells, as well as a small portion of the marl of the vicinity, with which Mr. Tuomey was 
kind enough to favor me. I mention this merely to show the importance of thoroughly 
searching the strata of the various localities before we conclude that we have all the 
species existing there. Attracted by the beauty of the larger shells, conchologists have 
very much neglected the more minute ones, which require a closer examination, and 
thus our knowledge of our fossil conchology is still limited. I may as well observe here, 
that I found the species met with in the sand from the cavities of the larger shells, in 
general, different from those in the loose marl. It is difficult to give a reason for this, 
unless there were species which usually inhabited the interior of dead shells, like the 
recent Valvata tricarinata, Say. 
In looking over these shells, I have been struck with the general resemblance which 
obtains between them and those of a corresponding age from Dax. This is peculiarly 
observable in the genera Acteon, Pasithea, &c. which are very numerous in both 
localities. ‘Their connexion is so close that in some cases they are scarce specifically 
distinct. 
