MOLLUSCAN FAUNA FROM THE CALCAREOUS MARLS 
IN THE VICINITY OF DE LAND, VOLUSIA 
CO., FLORIDA. 
BY WENDELL C. MANSFIELD. 
At the time of the preparation of the paper by Messrs. G. C 
Matson and F. G. Clapp, entitled .“A preliminary report on the 
geology of Florida, with special reference to the stratigraphy,”* it 
was recognized that knowledge of the pal^itologic content of the 
calcareous marls occurring in the vicinity of DeLand, Fla., was 
inadequate for accurately determining the geologic age of the beds. 
Therefore Dr. E. H. Sellards, State Geologist of Florida, at the 
request of Dr. T. Wayland Vaughan, made a careful collection in 
1908 at the marl' pit about one mile south of the city, and has fur- 
nished a detailed description of the exposure. The present report is 
based principally on the material obtained by Dr. Sellards, as the 
previous collections were procured mostly from well-borings, and is 
here published by permission of theJ)irector of the U. S. Geological 
Survey. 
Citations in literature to the fauna and geologic horizons at 
DeLand are few. The following are noted: “The Nashua marl 
is thought to rest uncoil formably upon the Miocene at DeLand ; but 
this opinion lacks confirmation, as the collections from that locality 
have not been studied in sufficient detail to determine the' exact age 
of the bedsd’f 
Log of the City Well at DeLand.t 
Material Thickness, feet Depth, feet 
“Sand, white 12 12 
Clay, yellow, sandy 10 22 
* Prepared in co-operation with the U. S. Geological Survey and the Flor- 
ida State Geological Survey, under the direction of T. W. Vaughan; Florida 
Geol. Surv., 2nd Ann. Report, pp. 21-173, 1909. 
tMatson, G. C., and Clapp, F. G., 2nd Ann. Report, Fla. Geol. Surv., 1909, 
p. 128. 
tMatson, G. C., U. S. G. S. Water Supply Paper No. 319, pp. 417-418, 1913. 
At the time this paper was printed, the author was engaged in field work 
and did not have the opportunity of reading the proof. (Ed.) 
Ill 
