269 
capsule columnar, 12 mm. long, abruptly narrowed into and tipped 
by the long (4~5 mm.) styles; seeds obovoid, 3-angled, 1.5 mm. 
long, marked with low broken transverse ridges. 
Missouri to Georgia, Florida and Texas; ascends to only a few 
meters above sea-level. 
Fossil Diatomaceae from Nebraska, and their Relation to 
modern Species.* 
By C. J. ELMoreE. 
Until very recently, fossil diatoms were scarcely known in 
Nebraska. In November, 1895, Dr. Barbour, professor of geology 
in the University of Nebraska, received some remarkably pure 
diatomaceous earth from Wheeler county. A little later he re- 
ceived some equally pure material from Mullen; and since that 
time a second deposit consisting of diatomaceous limestone has 
been found at Mullen, and a deposit of pure diatomaceous earth at 
Thedford. Some diatomaceous earth, largely calcareous, had been 
collected in Greeley county in 1887 by Mr. Russell and left with 
Dr. Bessey, but none of the species of diatoms that it contained 
had been identified. ee 
Very little is known of these deposits. Dr. Barbour has not 
yet visited them, and the information that can be obtained from 
the collectors, who, in some cases at least, are the owners of the 
land on which the deposits occur, is very limited. Possibly the 
Pure diatom deposits are of a sufficient extent to be valuable for 
‘commercial purposes, but this is somewhat doubtful. 
The pure diatom deposit at Mullen consists of three layers. 
The middle layer contains practically nothing but diatom valves, 
while the top and bottom layers are mixed with considerable 
foreign matter. In the top layer six species were found that were — 
not found in the middle layer, three of which are known in Ne- 
braska only as fossil. In the lower layer only three species were 
found which were not found in the middle layer, all of which are © 
common among modern Nebraska diatoms. It seems a little | 
Strange that the species in the lower layer should r esemble macs 
* Read before Nebraska Academy of Sciences, January 3, 1896. 
