STUDIES IN DIASPININE PYGIDIA. 
By E. W. STaFForD. 
Up to the present time the practice of staining Coccide in 
toto as an aid to taxonomic work has not been much adopted 
on this continent. Newstead and Green in their great Mono- 
graphs, recommend the use of stains, and in their preparation 
of specimens, stains are used. 
The Diaspine are classified for the most part on characters 
of the pygidia of the adult females. In my work with scale 
insects I found that one’s first tentatives toward the practice 
of staining are apt to be crowned with little positive success, 
but that after a little experimentation and practice, these 
artificial colors may be made to enhance the value of the mounts 
to such an extent as well to compensate for the extra labor 
involved in their application. 
Fic. 1—Types of Tubular Glands 
The chitinous paraphyses and the true marginal spines are 
not shown to better advantage in stained specimens than in 
those unstained. 
The marginal plates, the dorsal pores and the circum- 
gential pores are much more clearly defined in properly 
stained specimens than in those which have not been stained. 
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