68 Annals Entomological Society of America [Vol. VIII, 
The delicate tubular glands, which are practically invisible in 
unstained specimens, may be rendered clearly visible by proper 
staining. These tubules are in general different in different 
species and constant in the same species. Though they have 
been ignored by us, they nevertheless present a potentially 
valuable addition to our list of classificatory characters for the 
group. 
TECHNIQUE. 
Females were removed from under their waxy coverings and 
placed in strong cold aqueous solution of potassium hydroxide 
and allowed to remain until perfectly clear. This may require 
from two to five days. The specimens were then placed in a 
copious quantity of water for a couple of hours to remove all of 
the potassium therefrom. From the water they were trans- 
ferred to ninety-five per cent alcohol. From the alcohol, after 
plenty of time for dehydration, they were transferred to an 
alcoholic solution of Magentarot, (magenta-red), and allowed 
to remain about one hundred hours, or until they showed a 
purple color, but still remained translucent. They then were 
placed for a few seconds in absolute alcohol to wash off super- 
flous stain and transferred to xylol therefrom. 
After a couple of hours they were mounted in balsam or 
glycerine jelly. The above process entails little labor but 
extends over considerable time. 
The specimens may be boiled in strong potassium hydroxide 
for from fifteen minutes to half an hour, to procure the same 
degree of clarity and may be stained in Hamatoxylin solution 
von Delafield for ten or fifteen minutes. Thus the time of 
preparation may be much shortened. The former process has, 
however, given more desirable results. 
DORSAL-PORES. 
The pygidial pores in the Diaspine fall into two classes :— 
Larger, usually elliptic, grouped ‘“‘macropores,’’ and smaller 
or minute, circular, single, paired or grouped ‘‘micropores.”’ 
