HEM IP TER A. 
171 
this country; and Figure 21I, the hemispherical scale, 
Lecanium hemisphcericum (hem-i-sphaer'i-cum), which occurs 
in conservatories everywhere, and in the open air in Cali¬ 
fornia. 
The Armored-scales Sub-family Diaspince (Di-as-pi'nae).— 
The great majority of the common scale insects of this 
country differ from the forms described above in that the 
body of the insect, except for a very short period after 
birth, is covered with a scale composed in part of an excre¬ 
tion of the insect and partly of molted skins. Thus in the 
Lecaniums the scale-like object is the body of the insect; 
but in the case of the Oyster-shell Bark-louse, the Pernicious 
