198 NEW YORK STATE MUSEUM 



These masses are described as composed of " innumerable alga 

 filaments so intertwined and matted together as to form an outer 

 covering of almost felt-like consistency which could not however 

 be torn open without difficulty. This outer coating varied from 

 about ^ to /^ of an inch in thickness, and the interior of the 

 balls consisted so far as the naked eye could see only of mud. . . 

 A microscopic examination of the balls shows that they are com- 

 posed of a filamentous alga, Cladophoraglomerata. . . 

 The interior is seen to be filled with diatoms and the decomposing 

 inner ends of the radiating filaments ". Similar bodies, it is 

 stated, come from Ellesmere in Shropshire and from the lakes of 

 Sweden, Norway, northern Germany, Austria and upper Italy. 

 These so called lake balls while organically similar to the water 

 biscuit of Canandaigua lake, are entirely without calcareous de- 

 posit or inorganic njucleus. They would iseemi to* be comparable to 

 the condition of this water biscuit after the removal of the cal- 

 careous matter. While no explanation has been offered for the 

 peculiar glomerated mode of growth of the alga, it may be 

 that the noncalcareous lake balls have formed in waters without 

 excessive content of lime carbonate. That the deposition of this 

 lime carbonate in the formation of the water biscuit has gone on 

 pari passu with the growth of the alga, as above suggested, seems 

 quite clear. 



