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316 COLLEGE ENTOMOLOGY
These insects inhabit shrubs and trees chiefly but are also to be found in open
fields on various weeds, grasses, and similar perennial plants upon which they
feed and into whose tissues the females insert their somewhat club-shaped eggs
by means of a chisel-like ovipositor. The place of oviposition may be the bark
or wood of a tree, the midrib of a leaf, or the stem of a succulent plant, and
the eggs may be arranged in irregular groups or in rows in series of three to six
or more.
In the temperate regions the complete life history of five instars may require
six weeks, and there are from one to three broods a year. In the tropics there is
greater rapidity in growth and more continuous breeding. Most species excrete
honeydew, but only certain species attract ants which wait upon them much as
they do upon aphids. The members are more or less restricted in their feeding
to certain species or families of plants, and many have definite alternating hosts
upon each of which they spend a certain part of the year. As a group these insects
are not particularly injurious. In the cooler limits of their distribution
hibernation may be in the egg, nymph, or adult stage. The family reaches its
greatest development in the tropical areas of North and South America, Africa,
and Asia, and its zenith in South America. There are about 350 genera and a
great many species.
In Europe there are but two common genera, Centrotus Fab. and Gargora
Amyot and Serville, and two species, C. cornutus (Linn.) and G. genistre (Fab.).
In North America there are no less than 45 genera and 200 species. The most
important genera are Carynota Fitch, Ceresa A. and S., Cyrtolobus Goding,
Glossonotus Butler, Stictocephala Stal, and Thelia A. and S. The buffalo tree
hopper, Ceresa bubalus (Fab.), is the best known species although many others
are common and widely distributed. There are 40 species in Australia, including
many curious forms. Among them is Lubra regalis Goding which has large,
heavy pronatal processes resembling horns. In most of the species pronotal
horns or projections are present.
Family CERCOPIDlE 1 (Leach 1815) (Cer-cop'i-dre, from the Greek KepICos,
tail, + 1iJif;, appearance). German, Schildzirpen. Froghoppers, Spittlebugs,
Cuckoo Spit Insects.
These small insects derive their common names from the squatty, frog-like
appearance of the young and adults and from the fact that the immature forms
of certain genera are surrounded with and live in a mass of white froth or spittlelike
medium which is expelled from the anus.
The members are closely related to the CICADIDJE and are distinguished
by having but two ocelli; smooth tibire, the hind pair with one or two stout
fixed spines and a group of smaller ones at the apex; and lateral glands on abdominal
segments VII and VIII. They are all plant feeders and are cosmopolitan
in distribution but most abundant in the tropics. The most important
Holarctic genera are Aphrophora Germar, Cercopt's Fabr., Clastoptera Germar,
I'This family as formerly conceived has recently been raised to superfamily rank with four
families of which one retains the above name.