-1897.] Natural Impuilses. 585 
as a whole was regarded as the agent at once reproducing and 
preserving the original form, these functions nowadays are at- 
tributed to a certain class of its constituting cells, or rather to 
the protoplasma which they contain. 
But a scanty comfort it is, that this theory affords to our 
mind eager to penetrate into this apparently unfathomable 
secret of nature, intimately connected with the question for the 
origin of life itself; but notwithstanding its deficiencies, the 
hypothesis of reproducing cells well explains the resemblance 
commonly existing between members of one family, its increas- 
ing in nearly related individuals and its diminishing by the 
interference of strange elements. 
If permitted to consider the “ cell” as the elementary organ 
in animals and vegetables, we are as well justified to attribute 
the same roll in the mineral world to the “ crystal.” There is 
no mineral substance existing which is not known to crystal- 
lize under certain circumstances, and the formation of cells in 
plants from the constituents of their juices, the secretion of 
muscular fibre from albuminous matter in blood, stands in 
closer relation to the separation of crystals from solutions, 
than is generally imagined. Who, when on a cold winter 
morning, finding the panes of his windows covered with ice- 
crystals shaped like luxurious ferns, mosses or twigs of pine 
trees, was not impressed with the conjecture of a relation be- 
tween the phenomena of organization and crystallization of 
some common occult force giving form to organic as well as to 
nonorganic matter? Indeed, thereare no strict limits existing 
between organization and crystallization. The curved lineand 
surface may be regarded as particular to and characteristic of 
organic matter, the straight line and surface of mineral sub- 
stances, but there are innumerable exceptions exhibiting the 
former in well defined crystals, while crystals of minerals fre- 
quently occur having curved surfaces. Thus the crystals of 
pyromorphite, chiefly consisting of phosphate of lead, are poly- 
hedra with curved planes, and compounds of hydroxylamine 
with certain oxides of metals have hemispheric forms. The 
starch grain may be considered as the connecting link between 
both morphological classes, the round form on the one hand 
41 
