586 The American Naturalist. [July, 
indicating a cell like character, its growing by attachment of 
layers on its outside on the other hand, perfectly agreeing with 
the way in which crystals are observed to grow. 
It is in three states that solid matter is known to occur, in 
the amorphous, the crystalline and the organized states. The 
amorphous seems to be the original one, since the others are 
generally found to originate from it, the reverse but exception- 
ally taking place. The best known amorphous substance is 
glass, in which in its perfect state no crystalline particles can 
be discovered. Resins, such as colophony and copal, and 
Indian rubber are amorphous, as well as glue and molten 
sugar in its fresh state. In sugar the liability to pass into the 
crystalline state is very prominent; sometimes a few minutes 
after its cooling the transparent mass becomes opaque by the 
separation of minute crystals of sugar. Crystallization fre- 
quently sets in in some varieties of glass, particularly when 
rapidly cooled. Albumen -is the principal amorphous sub- 
stance in living animals from which organized matter is 
derived. 
A striking difference of amorphous and crystalline matter is 
manifested in the behavior of their solutions. Amorphous 
matter soluble in water, when dissolved gives viscid or gela- 
tinous liquids, their thickness increasing with the lessening 
amount of water present. No compounds with water in defi- 
nite proportions seem to be existing. Solutions of crystalline 
matter, on the contrary, are thin as water; when concentrated 
to a certain point crystals of solid matter begin to separate. 
Crystallization sometimes sets in suddenly, the whole liquid 
turning into a magma of small solid particles suspended in the 
fluid. The solution contains compounds with water in defi- 
nite proportions. When evaporating a solution of red cobalt 
chloride, it suddenly turns blue, which happens in the moment 
when more water has been removed, than the red salt needs 
for its existence. 
Having tried to explain the resemblance in the features of 
related organisms by the prevailing of particular cells repro- 
ducing by unknown impulses the same character in every new 
individual, we feel induced to look for the cause of the well 
