130 
FLORIDA STATE GEOLOGICAL SURVEY. 
Structure:—The Nashua marl is exposed at only a few localities 
in the St. Johns Valley and it is difficult to form any definite idea con¬ 
cerning its structure. It has probably been subjected to the same de¬ 
formation as the Caloosahatehee marl, but the isolated-exposures 
afford no opportunity to observe evidences of folding. The dip is 
doubtless seaward and it is probably very slight. 
Local DetailsIn the St. Johns Valley there are a number of-ex¬ 
posures of the Pliocene marl which have been designated the Nashua 
marl. At the type locality, one-fourth mile south of Nashua, Putnam 
County, there is an exposure of five feet of white sand, resting un- 
conformably upon about fifteen feet of white shell marl. From this 
locality was obtained the list of fossils given below : 1 
Terebra protexta Conrad. 
Terebra dislocata Say. 
Terebra concava Say. 
Conus marylqndicus Green. 
Oliva literata Lamk. 
Olivella mutica Say. 
Marginella pardalis Dali. 
Volutella amiantula Dali. 
Fulgur maximum Conrad. 
Eupleura miocenica var. intermedia 
Dali. 
Murex pomum Linn. 
Ilyanassa porcina Say. 
Ilyanassa isogramma Dali. 
Ilyanassa granifera Conrad. 
Nassa scalaspira Dali. 
Anachis avara var. calossaensis Dali. 
Turbonilla. 
Eulima. 
Cerithiopsis greeni C. B. Ads. 
Crucibulum auricula Gmel. 
Crepidula convexa Say. 
Natica ( Cryptonatica ) pusilla Say. 
Littorina irrorata Say. 
Dentalium carolinense Conrad. 
Area (Noetia ) limula var. platyura 
Dali. 
Area campyla Dali. 
Ostrea virginica Gmel. 
Pecten madisonius Say. 
Anomia simplex Orb. 
Crassinella lunulata Conrad. 
Crassinella acuta Dali. 
Phacsides tuomeyi Dali. 
Phacoides multilineatus T. and H. 
Divaricella chipolana Dali var.? 
Cardium robustum Sol. 
Venus tridacnoides Lam. 
Dosinia, young— D. elegans Conrad? 
Chione cancellata Linn. 
Gemma magna Dali. 
Pit aria? young. 
Mulinia congesta Conrad. 
Mulinia congesta. var. triquetra Con¬ 
rad. 
Corbula cuneata Say. 
Geologic Age:—“Pliocene, the presence of Pecten madisonius sug¬ 
gests the presence of Miocene in the same bluff. The fauna has an 
additional interest in containing species found in the ‘Waccamaw beds,’ 
but not in the Caloosahatchee.” (Vaughan.) 
One-half mile above the Atlantic Coast Line Railroad bridge over 
St. Johns River in Putnam County, there is a bluff which rises from 
three to eight feet above high water. At this locality, the Pliocene 
Nashua marl is well exposed and abundantly fossiliferous. Dr. 
Vaughan’s list of fossils collected from this locality follows: 
1 Determined by Dr. Vaughan. 
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