12 NATURALISTS’ ASSISTANT. 
arsenical soap. The opening can then be covered with a bit 
of zoldbeater’s skin. 
Exact labels giving the name of the bird laying the eggs, 
the locality and date, the number of eggs in the nest, etc., 
should be kept with each specimen and numbered to corre- 
spond with a number placed on the egg. 
Eggs of our native birds taken at various stages of incu- 
bation, the shell cracked and then the whole placed in 40 
per cent. alcohol and in a few hours transferred to fresh and 
slightly stronger spirit, and then after a day or two to alcohol 
of 70 to 80 per cent., would be very desirable in every 
museum of the world. Of course, with each egg’ should be 
preserved not only the name of the species, but also the 
number of hours since incubation began. ‘Thus the student 
will be able to trace more or less completely, according to 
the amount of material at command, the deveiopment of the 
various forms of which, at present, comparatively little is 
known. ‘The same process may be advantageously followed 
with the eggs of other animals, and in dissecting mammals 
all embryos should be carefully preserved. 
- REPTILES AND BATRACHIA. 
The collection of snakes, turtles, lizards, frogs, toads, 
and salamanders is not accompanied with any special difficulty 
though proper precautions should be taken against venomous 
serpents. Various species of each group affect certain lo- 
calities, some living on land and others in the water. Some 
live in the open fields, others in thick woods, while still others 
