KANSAS ACADEMY OF SCIENCE. 67 
Ill. BIOLOGY. 
SOME DIATOMACEA OF KANSAS. 
BY GEO. H CURTIS, MCPHERSON. 
DIATOMACE# OF GAGE’S POND, TOPEKA, AND OF SILVER LAKE. 
Read before the Academy, at McPherson, December 29, 1899. 
Although the Diatomacez of the eastern United States have been pretty 
thoroughly investigated by several competent observers, I believe that little is 
known as to what forms exist in the West. With the exception of Thomas and 
Chase’s catalogue of the Diatomacez of Lake Michigan, which embraces 34 
genera and 214 species, and my own catalogue of the Cincinnati forms, 42 
genera and 972 species, there are no investigations of western or central-west- 
ern forms known to me. 
Under these circumstances, perhaps a short paper upon Kansas forms may 
possess sufficient interest to justify reading it. 
In company with Mr. Frank Patrick, I paid a visit to Gage’s pond, in the 
western suburbs of Topeka, about the middle of October. It was dug by Mr. 
Gage a number of years ago asa fish-pond and stoned up. I did not think of 
estimating its dimensions while there, but is perhaps 150 feet long by 50 feet 
wide, and two or three feet deep. Our object in visiting it is was to ascertain if it 
contained diatomaceous material; and, while there, I made a gathering which, 
when cleaned up a few days afterward, yielded some very interesting slides, and 
some Navicule not previously met with elsewhere. 
The most abundant form in the gathering was L'pithemia gibba, both the 
long and the short varieties. The most common Navicula was radiosa. Cym- 
bella stomatophora of several sizes was also common; and Amphipleura 
pellucida, a rare form, more than usually abundant. My gathering was made 
on the east side, about midway; and it was rather curious that there was no 
Amphipleura in Mr. Patrick’s gathering, made only a short distance away at 
the south end, or from the under sides of the leaves of the water-lilies, of which 
many were growing in the pond. Synedra ulna, var. longissima, was abun- 
dant, especially in Mr. Patrick’s gathering. Gomphonema was rather rare. 
There were a considerable number of large, somewhat curved, sponge spicules. 
Navicula cuspidata was a prominent form—both the long and the short varie- 
ties. Cymbella, usually one of the most abundant forms in any gathering East, 
was very scarce at Gage’s pond, as well as Gomphonema. 
- The most noticeable thing about the gathering was the remarkable predomi- 
nance of the rare form, Hpithemia gibba, of which there were, in a field taken 
at random, under a quarter-inch objective, no less than seventy-eight individuals, 
as compared to nine Cymbelle, four Navicule, thirteen Synedre, and four 
Denticule —almost three times as many as all the other forms together. 
As some may not have had experience with the microscope, I would say that 
the field of view mentioned above was round, and one-fiftieth of an inch in 
diameter. This will convey some idea of the exceedingly minute size of these 
diatoms: that 108 of them, as mentioned above, could, without any crowding 
whatever, be placed in a circle of that size. 
