1897 THE MICROSCOPE. 13 
specimens are foundin the larva of the dytiscus, cock- 
chafer, blow-fly, goat moth, silk worm and house-cricket. 
Iodo-Sulphate of Quinine.This beautiful crystilliza- 
tion for the polariscope may be prepared .as follows: Mix 
3 drachms of pure acetic acid with 1 drachm of alcohol; 
add to these 6 drops of dilutedsulphuric acid(1to9.) One 
drop of this fluid is to be placed on a glass slide and the 
merest atom of quinine added, time given for solution to 
take place; then upon the tip of a very fineglass rod a very 
minute drop of tincture of iodine is to be added. After a 
time the polarizing crystals of iodo-sulphate of quinine are 
slowly produced without the aid of heat. 
Crystalizations of Santonine.—Santonine may be pro- 
cured from any drug store. It is a vermifuge. It is an 
alkaloid derived from Semen Cynae or worm seed. It is 
soluble in alcohol, chloroform and water. Each solvent 
alters the character of the crystalization. With chloro- 
form it assumes a lace-like appearance; with water it ar- 
ranges itself in tufts composed of small oblong plates ar- 
ranged around a nucleus; crystallized on a hot slide crys- 
talizations radiating from a centre will be formed. 
The Difference Between Crystals and Crystalization: 
A crystalization is an arrangement of the particles of a 
substance composed of many thousandsof crystals. Nearly 
every substance has a definite manner of crystallizing. 
The individual crystals always belong to a certain system. 
To detect the substance and to determine an adulteration 
beyond all doubt these individual crystals should be ob- 
tained. 
SU rEN CE GOSSIP. 
Microbes in River Water.—Mr. Hawkins, the bacteriol- 
ogist to the Indian Northwest and Central Provinces, 
states, in Zhe Popular Science News, that, from bacterio- 
logical observations that he has made, he has come to the 
conclusion, that, whilst in England, the more muddy a 
