LIBRARY

520
COLLEGE ENTOMOLOGY
The larva:! of many species pupate in a cell in the ground, burrow in wood, or
, other secluded places; while certain leaf weevils spin lace-like cocoons from a
sticky quick-drying fluid taken from the anal opening by the mandibles and
slowlY and skillfully woven. The normal life cycles may be very short, requiring
from one to four generations a year, or may be quite long, involving from
one to five years for a single complete life history. Rarely from 25 to 30 years
have been recorded for certain wood-boring beetles. Hibernation and restivation
may occur in all the various stages.
The fossil record may be summarized as follows:
Order PROTOCOLEOPTERA Tillyard 1924, from Upper Permian, Belmont,
New South Wales. Early ancestors. .
Trias, Upper - Ipswich, Australia - Beetles abundant.
Liassic - Europe - abundant.
Jurassic, Upper - Europe - abundant.
Tertiary - North America - abundant.
Eocene - many modern genera occur.
Baltic Amber - nearly 500 species known.
Miocene - Florissant, Colo. - nearly 1,000 species known.
BASIS FOR CLASSIFICATION FOR COLEOPTERA
1. Character of the Exoskeleton and Elytra: Whether hard and heavily scleratized
or soft and leather-like; the surface, whether smoothed and polished
or pubescent, hairy, scaly, punctured, pitted, rugose, ribbed, or striated;
length of elytra, whether covering or only partially covering the abdomen.
The wing venation is also used to some extent in separating families.
2. Antennre: The shape of the antenna:! is exceedingly variable and may be
setiform or awl-like and filiform or thread-like, in which all segments are
more or less alike and gradually diminish in size to a point apically;
moniliform, or with the segments rounded and bead-like; serrate, or with
the segments extending laterally on the outside like saw-teeth; clavate, in
which the segments gradually increase in size apically to form a club;
capitate, ending in usually three to five large loose or fused segments which
form a terminal enlargement or ball-like structure; geniculate or elbowed,
consisting of a small basal segment and the longest segment forming the
!'lcape, followed by a short pedicel and a number of small ring-joints and
segments composing the flagellum (these segments are often held at an
angle to the scape); lamellate geniculate or capitate types, in which the
apical portion is composed of a number of lamellre that fit together like
leaves of a book; pectinate, where the segments have long lateral slender
extensions so as to produce a comb-like appearance and occurring usually
in males. The position of the insertion of the antennre on the head is also
important.
:1. Abdominal Stemites: In these closely joined insects there is a fusion of
segments at the base and apex of the abdomen with the result that the