LIBRARY

HEMIPTERA 345
veloped, reduced, or atrophied and with or without segmentation; the fore pair
may be greatly enlarged and fossorial and the only pair present in certain rare
forms; tarsi one- or two-segmented; thoracic and abdominal spiracles present
in all stages; anus dorsal or apical;
anal tube obscure or well developed.
Males have conspicuous or
poorly formed compound eyes,
and a pair of ocellanre may be
present in some forms; antennre
lO-segmented, simple or pectinate;
hal teres with from four to
six curved apical bristles.
The family is a comparatively
small one but is widely distributed
in all parts of the world. The
most important genera are: Aspidoproctus
Newstead, Calli pappus
Guerin, I cerya Signoret, Kuwania
Cockerell, Llaveia Signoret, Margarodes
Guilding, M atsucoccus
Cockerell, Monophlebus Burmeister,
and Xylococcus Loew.
The largest specimens, which
belong to the genera Llaveia and
Callipappus, measure up to 25
mm. in length. The former occurs
mostly in tropical America with a
representative in the Philippine
Islands. The most interesting
member of this genus is L. axin
(Llave) of Mexico from which a
fatty substance and acid obtained
by the natives are used for making
varnish and as a resolvent for
healing wounds. Callipappus is
Australian. In the two species
C. australis Maskell and C. westwoodi
Guerin, the females measure
up to 25 mm. and the males
have a wing expanse of 12 mm.
FIG. 119. A string of South African ground
pearls or cysts of the subterranean coccid. M OTgarodes
capensis Giard, and a single cyst greatly
enlarged. . These beads are the color of old gold,
and are very light, and do not discolor the clothes
or skin of the wearer.
The latter are red with rosy wings and are commonly called "Bird of Paradise
flies" (Tillyard, 1926).
The very young larvre of Aspidoproctus cinerea (Green) .and related species
of India have a fringe of long. transparent wax filaments around the body and
are carried by the wind like thistledown (Lefroy, 1909).