Tue Microscope. 163 
parasites from birds and small mammals may be obtained by 
slitting the intestine open in a dish of water. 
The above are a few examples of materials easily within 
the reach of any one possessing a microscope. If they are 
handled as directed in the preceding pages the beginner cannot 
fail of success, and with patience and perseverance he will soon 
acquire a knowledge of the microscope and microscopic tech- 
nique that will always prove a source of pleasure and profit. 
In this busy life we cannot spend too much time observing 
Nature and learning her ways. ‘“ People grow better,” says 
Daudet, *“‘ for listening to Nature, and those who love her do 
not lose their interest in men.” 
Whatever brings us closer to Nature’s heart, brings us 
nearer to that Supreme Being who has created all things.— 
W. P. Manron. 
CONTENTS OF AN OVARIAN OYST. 
They can without the microscope be distinguished from as- 
citic fluid by the fact that, even after twenty-four hours, they 
do not coagulate like the latter. 
With the microscope we find in the liquid of an ovarian 
cyst, almost constantly, almost pathognomonically, ced/s meas- 
uring five to thirty », with a granular appearance, and frequent- 
ly with plainly distinguishable fat-globules ; occasionally choles- 
terin crystals, well crystallized ; leucocytes, red blood-corpuscles, 
fat-globules; colloid concretions in cysts with inspissated con- 
tents (they have an irregular shape, are homogeneous, and of a 
pale-yellow collor); detritus in cysts which have been repeat- 
edly punctured; czdiated cells (important for differential diag- 
nosis from ascites) lining the walls of the cyst; pavement epi- 
thelium is not of diagnostic value, the serous membranes having 
the same lining.—PEYER. 
THE SIZE OF THE SPIDER’S THREAD. 
I have often compared the size of the thread spun by full 
grown spiders with a hair of my beard. For this purpose I 
placed the thickest part of the hair before the microscope, and 
from the most accurate judgment I could form, more than a 
hundred of such threads placed side by side could not equal the 
