NATURAL HISTORY AND PHYSIOGRAPHY OF NEW BRUNSWICK. 305 
It is a coincidence that I was asked by a correspondent a year 
or two earlier whether the mode of formation of somewhat 
similar balls which occur in Flint or Sandy Pond in Lincoln,. 
Massachusetts, is known. The balls which occur there, as 
shown by the small specimen photographed beside the Kedron 
Lake ball, are of much finer texture than that from Kedron Lake, 
and they are apparently composed chiefly of the tangled stems 
and leaves of the Duckgrass ( Eriocaulon septangnlare ) , with 
perhaps also some other materials. They are homogenous in 
structure, without any apparent nucleus. They are described by 
Thoreau in his ‘‘Walden” (Chapter IX), who shows (and the 
observation is confirmed by two correspondents who have written 
me concerning them), that they are formed upon a sandy bottom 
much as described by Mr. Davis. From these two cases one 
would infer that such balls must be of frequent occurrence in 
shallow sandy lakes. Having, however, inquired of my botanical 
friends without learning of any other localities or of any pub- 
lished description of their mode of formation, I inserted in Science 
for April 8th a letter of inquiry, asking for information as to 
other localities, local names for them, published references to, 
or descriptions of them, materials of which they are composed, 
etc. In response, I have received but very scanty information, 
including only a single reference to another locality for them — a 
lake in Idaho. 
It would be remarkable if no description of these balls other 
than Thoreau’s, nor any account of their mode of formation, has 
been published, yet such appears to be the case. Presumably 
the}' are nothing more than the result of the rolling about of 
vegetable fragments on hard sandy bottoms by the action of the 
under-water parts of waves. Probably, as one of my correspond- 
ents suggests, the material collects first in ripple-marks, there 
becoming somewhat matted together in short loose cylinders ; as 
these enlarge they are rolled out and over the bottom, where, 
gathering other material, they gradually become larger, rounder, 
and more compact. It is not improbable that micro-organisms 
develop within them, and, by forming zoogloea or other glutinous 
matter, help to fasten them together. It would be worth while, 
