THE MUSEUM 
OF 
NATURAL HISTORY. 
ZOOLOGY. 
Class V. — INSECTS (Insecta). 
In the following pages I intend to give, as far as space 
and other circumstances admit, a general view of the 
various orders of true Insects. B}' true is meant 
Insects, as distinguished from Crustacea (such as 
Lobsters, Shrimps, Crabs), Spiders (including Mites), 
Centipedes (or Myriapoda), and such like, which are 
all insects in the strict sense of the term ; that is, all 
Fig. 47. 
Fig. 48. 
One of the Entomostracous Crustacea, 
showing very clearly annulose structure. 
Larva of a Beetle, 
showing the an> 
nulose structure. 
these classes have the body composed of many seg- 
ments or rings (annuli)— hence their general name of 
Annulosa : while their various parts, such as the 
antennse, organs of the mouth and head, thorax and its 
appendages, are all formed of various parts or joints, 
as may be seen by looking at a Lobster, a Centipede, 
or at any Beetle — even the “black beetle” of the 
kitchen, the Cockroach, which, however, we find be- 
longs to a different order to that containing the “ great 
army” of Beetles — see figs. 47, 48, and 49. 
Jointed feet are strikingly indicative of annulose 
structure, and, hence, many naturalists call them Con dy- 
uopa, or creatures with jointed feet. In dividing the 
invertebi'ated classes (those, namely, which have no 
real skeleton), we must hardly compare them with the 
vertebrated animals. Insects are organized on a totally 
different plan. Most vertebrated animals have tlieir 
nervous system deranged, or destroyed by any injury 
to the spine ; but insects, or rather annulose animals 
like insects — Spiders, Crabs, and Centipedes — are very 
little, if at all, seriously injured in this way. The 
nervous matter in Annulosa is collected in ganglia all 
along the body, and I might enter on this ganglionic 
Fig. 50. 
structure were animal anatomy my object. Most of 
the Annulosa undergo great changes in iheir course of 
